1995 JEEP CHEROKEE Stop light

REAR LIGHTING
TAIL LAMPS AND REAR LICENSE PLATE LAMPS
Circuit A3 from fuse 5 in the Power Distribution
Center (PDC) connects to a bus bar in the fuse block
which feeds circuit L7. Fuse 15 in the fuse block pro-
tects circuit L7.
The headlamp switch has three positions: ON,
PARK (parking lamps) and OFF, plus a dimmer
switch. When the headlamp switch is in the PARK or
ON position, the switch connects circuit L7 to circuit
L90. From the headlamp switch, circuit L90 branches
to power the front parking lamps and rear tail
lamps, side marker lamps, and rear license plate
lamps.
GROUND CIRCUIT
Circuit Z1 provides a ground for the parking lamps,
tail lamps, and rear license plate lamps.
HELPFUL INFORMATION
²If the vehicle is equipped with factory installed
trailer tow, circuit L90 splices to the trailer tow har-
ness.
²Check fuse 5 in PDC.
²Check fuse 15 in the fuse block.
²When the headlamp switch is in the PARK or ON
position, circuit L7 also connects to circuit E2. Cir-
cuit E2 continues through fuse 19 in the fuse block.
Circuit E2 powers the illumination lamps.
STOP LAMPS AND CHMSL LAMPS
Circuit L9 from fuse 4 in the Power Distribution
Center (PDC) connects to the stop lamp switch.
When the operator depresses the brake pedal, the
stop lamp switch closes and connects circuit L9 to
circuit L50. Circuit L50 connects to the stop lamps
and Center High Mounted Stop Lamps (CHMSL).
Circuit Z1 provides a ground for the stop lamps and
CHMSL lamps.
HELPFUL INFORMATION
²Check fuse 4 in the PDC.
²Check for continuity across the stop lamp switch
when it is closed.
BACK-UP LAMPS
In the START or RUN position, the ignition switch
connects circuit A1 from fuse 6 in the Power Distri-
bution Center (PDC) to circuit A21. Circuit A21 feeds
a bus bar in the PDC that powers circuit F12
through fuse 11.
Circuit F20 supplies power to the back-up lamp
switch. On automatic transmission equipped vehicles,
the back-up lamp switch is part of an assembly that
includes the PARK/NEUTRAL position switch. When
the operator puts the transmission in REVERSE, the
back-up lamp switch connects circuit F20 to circuit
L10. Circuit L10 feeds the back-up lamps. Circuit Z1
provides ground for the back-up lamps.
HELPFUL INFORMATION
²Check fuses 6 and 11 in the PDC.
²Check for continuity across the back-up lamp
switch when it is closed.
DIAGRAM INDEX
Component Page
Back-Up Lamps........................8W-51-4, 5
Back-Up Lamp Switch.....................8W-51-2
Center High Mounted Stop Lamps (CHMSL).......8W-51-3
Fuse 15 (Fuse Block)......................8W-51-2
Fuse 4 (PDC)...........................8W-51-3
Fuse 6 (PDC)...........................8W-51-2
Fuse 7 (PDC)...........................8W-51-2
Fuse 11 (PDC)..........................8W-51-2
Headlamp Switch.........................8W-51-2
Ignition Switch..........................8W-51-2
License Plate Lamp.......................8W-51-3
Park/Neutral Position Switch.................8W-51-2
Side Marker Lamps.....................8W-51-4, 5
Stop Lamp Switch........................8W-51-3
Tail/Stop Lamps........................8W-51-4, 5
Turn Signal Lamps......................8W-51-4, 5
J8W-51 REAR LIGHTINGÐXJ VEHICLES 8W - 51 - 1

WIPERS
INDEX
page page
Diagram Index............................ 2
Rear Wiper System......................... 1WipersÐIntermittent........................ 1
WipersÐStandard.......................... 1
WIPERSÐSTANDARD
A circuit breaker powers the standard wiper sys-
tem. The standard wiper system operates at either
LOW or HIGH speeds.
In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 from fuse 6 in the Power
Distribution Center (PDC) with circuit A48. Circuit
A48 supplies voltage to circuit F86 through the circuit
breaker near the left kick panel.
Circuit F86 is double crimped at the circuit breaker
and supplies power to the wiper switch and the park
switch in the wiper motor. Circuit Z1 from the wiper
motor provides ground for the wiper motor and
switch.
When the operator moves the wiper switch to the
LOW position, battery voltage passes through the
switch to circuit V3. Circuit V3 feeds the wiper motor
low speed brushes. If the operator selects wiper
HIGH speed operation, the wiper switch passes cur-
rent to circuit V4. Circuit V4 feeds the wiper motor
high speed brushes.
As the windshield wiper motor turns, the park
switch, internal to the motor, moves from its DOWN
position to the UP position. When the wiper switch is
turned OFF, the V55 circuit prevents the wipers from
stopping in any position but park.
The windshield washer uses a pump motor located
inside the windshield washer fluid reservoir. When
the washer switch is pressed, power is supplied
through the wiper switch to the pump motor on cir-
cuit V10. Circuit Z1 provide ground for the pump
motor.
HELPFUL INFORMATION
Circuit Z1 also provides ground for the rear wiper
washer pump, radiator fan motor and front end light-
ing.
WIPERSÐINTERMITTENT
A circuit breaker powers the standard wiper sys-
tem. The intermittent wiper system operates at either
LOW or HIGH or DELAY speeds.
In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 from fuse 6 in the PDC
with circuit A48. Circuit A48 supplies voltage to cir-
cuit F86 through the circuit breaker near the left kick
panel.Circuit F86 is double crimped at the circuit breaker
and supplies power to the wiper switch and the park
switch in the wiper motor. Circuit Z1 from the wiper
motor provides ground for the wiper motor and
switch.
When the operator moves the wiper switch to the
LOW position, battery voltage passes through the
switch to circuit V3. Circuit V3 feeds the wiper motor
low speed brushes. If the operator selects wiper
HIGH speed operation, the wiper switch passes cur-
rent to circuit V4. Circuit V4 feeds the wiper motor
high speed brushes.
The DELAY portion of the wiper switch contains a
variable resistor. The variable resistor connects to the
intermittent wiper module through the wiper switch
harness. The amount of delay selected by the operator
determines the voltage drop through the resistor and
the voltage level received by the intermittent wiper
module.
After the intermittent wiper control module deter-
mines the amount of delay selected, it cycles the
wipers by periodically energizing circuit V3. Circuit
V3 powers the wiper motor low speed brushes.
As the windshield wiper motor turns, the park
switch, internal to the motor, moves from its DOWN
position to the UP position. When the wiper switch is
turned OFF, the V55 circuit prevents the wipers from
stopping in any position but park.
The windshield washer uses a pump motor located
inside the windshield washer fluid reservoir. When
the washer switch is pressed, power is supplied
through the wiper switch to the pump motor on cir-
cuit V10. Circuit Z1 provides ground for the pump
motor.
HELPFUL INFORMATION
Circuit Z1 also provides ground for the rear wiper
washer pump, radiator fan motor and front end light-
ing.
REAR WIPER SYSTEM
In the RUN position, the ignition switch connects
circuit A1 from fuse 6 in the PDC with circuit A38.
Circuit A38 connects to a fuse block bus bar that
powers circuit V15 through the fuse in cavity 1. Cir-
cuit V15 supplies power to the rear wiper switch.
J8W-53 WIPERSÐXJ VEHICLES 8W - 53 - 1

DIAGRAM INDEX
Component Page
Chime/Buzzer Module......................8W-50-6
Dimming Module.........................8W-50-9
Dimming Relay..........................8W-50-8
Fog Lamp Relay........................8W-50-10
Fog Lamp Switch........................8W-50-10
Fuse 5 (Fuse Block).......................8W-50-7
Fuse 5 (PDC).........................8W-50-4, 8
Fuse 6 (PDC).........................8W-50-6, 8
Fuse 7 (PDC)..........................8W-50-10
Fuse 9 (Fuse Block).......................8W-50-4
Fuse 10 (Fuse Block)......................8W-50-7
Fuse 11 (Fuse Block)......................8W-50-8
Fuse 13 (PDC).........................8W-50-10
Fuse 20 (Fuse Block)......................8W-50-8
Fuse 26 (Fuse Block)......................8W-50-6
Headlamp Delay Module....................8W-50-7
Headlamp Dimmer Switch.................8W-50-4, 7
Headlamp Switch.....................8W-50-4, 7, 9
Headlamp Relay.........................8W-50-9
Ignition Switch........................8W-50-6, 8
Instrument Cluster........................8W-50-5
Left Fog Lamp.........................8W-50-10
Left Headlamp..........................8W-50-5
Left Marker Lamp........................8W-50-5
Left Tail, Stop and Turn Signal Lamp............8W-50-5
Overhead Console......................8W-50-4, 8
Right Fog Lamp........................8W-50-10
Right Headlamp.........................8W-50-5
Right Tail, Stop and Turn Signal Lamp...........8W-50-5
Telltale Connector (Instrument Cluster)...........8W-50-9
J8W-50 FRONT LIGHTINGÐXJ-RHD 8W - 50 - 3

REAR LIGHTING
TAIL LAMPS AND REAR LICENSE PLATE LAMPS
Circuit A3 from fuse 5 in the Power Distribution
Center (PDC) connects to a bus bar in the fuse block
which feeds circuit L7. Fuse 9 in the fuse block pro-
tects circuit L7.
The headlamp switch has three positions: ON,
PARK (parking lamps) and OFF, plus a dimmer
switch. When the headlamp switch is in the PARK or
ON position, the switch connects circuit L7 to circuit
L90. From the headlamp switch, circuit L90 branches
to power the front parking lamps and rear tail
lamps, side marker lamps, and rear license plate
lamps.
GROUND CIRCUIT
Circuit Z1 provides a ground for the parking lamps,
tail lamps, and rear license plate lamps.
HELPFUL INFORMATION
²Check fuse 5 in PDC.
²Check fuse 9 in the fuse block.
²When the headlamp switch is in the PARK or ON
position, circuit L7 also connects to circuit E2. Cir-
cuit E2 continues through fuse 25 in the fuse block.
Circuit E2 powers the illumination lamps.
STOP LAMPS AND CHMSL LAMPS
Circuit L9 from fuse 4 in the Power Distribution
Center (PDC) connects to the stop lamp switch.
When the operator depresses the brake pedal, the
stop lamp switch closes and connects circuit L9 to
circuit L50. Circuit L50 connects to the stop lamps
and center high mounted stop lamps (CHMSL). Cir-
cuit Z1 provides a ground for the stop lamps.
HELPFUL INFORMATION
²Check fuses 13 in the PDC.
²Check for continuity across the stop lamp switch
when it is closed.
BACK-UP LAMPS
In the START or RUN position, the ignition switch
connects circuit A1 from fuse 6 in the Power Distri-
bution Center (PDC) to circuit A21. Circuit A21 feeds
a bus bar in the PDC that powers circuit F12
through fuse 11.
Circuit F12 supplies power to the back-up lamp
switch. On automatic transmission equipped vehicles,
the back-up lamp switch is part of an assembly that
includes the PARK/NEUTRAL position switch. When
the operator puts the transmission in REVERSE, the
back-up lamp switch connects circuit F12 to circuit
L10. Circuit L10 feeds the back-up lamps. Circuit Z1
provides ground for the back-up lamps.
HELPFUL INFORMATION
²Check fuses 6 and 11 in the PDC.
²Check for continuity across the back-up lamp
switch when it is closed.
DIAGRAM INDEX
Component Page
Center High Mounted Stop Lamps (CHMSL).......8W-51-3
Fuse 4 (PDC)...........................8W-51-3
Fuse 5 (PDC)...........................8W-51-2
Fuse 6 (Fuse Block).......................8W-51-2
Fuse 6 (PDC)...........................8W-51-2
Fuse 9 (Fuse Block).......................8W-51-2
Headlamp Switch.........................8W-51-2
Ignition Switch..........................8W-51-2
Left Back-Up Lamp.......................8W-51-4
Left Side Marker Lamp.....................8W-51-4
Left Tail/Stop Lamp.......................8W-51-4
Left Turn Signal Lamp.....................8W-51-4
License Plate Lamp.......................8W-51-3
Park/Neutral Position Switch.................8W-51-2
Right Back-Up Lamp......................8W-51-5
Right Side Marker Lamp....................8W-51-5
Right Tail/Stop Lamp......................8W-51-4
Right Turn Signal Lamp....................8W-51-5
Stop Lamp Switch........................8W-51-3
J8W-51 REAR LIGHTINGÐXJ-RHD 8W - 51 - 1

CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn the engine
OFF.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1 379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedures on each cylinder ac-
cording to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
Refer to the Cylinder Combustion Pressure Leak-
age Test Diagnosis chart.
INSPECTION (ENGINE OIL LEAKS IN GENERAL)
Begin with a through visual inspection of the en-
gine, particularly at the area of the suspected leak. If
an oil leak source is not readily identifiable, the fol-
lowing steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for ap-
proximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified, re-
pair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24km (15 miles), and
repeat step (3).
If the oil leak source is not positively identi-
fied at this time, proceed with the air leak detec-
tion test method as follows:
(1) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(2) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(3) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(4) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is de-
tected and identified, repair per service manual pro-
cedures.
(5) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(6) If no leaks are detected, turn off the air supply
and remove the air hose and all plugs and caps. In-
stall the PCV valve and breather cap hose. Proceed
to step 7.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the en-
gine, a more involved inspection is necessary. The fol-
lowing steps should be followed to help pinpoint the
source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, distributor seal,
camshaft bore cup plugs oil galley pipe plugs, oil
9 - 6 ENGINESJ

(2) Remove fitting from pump housing (Fig. 10).
Prevent flow control valve and spring from
sliding out of housing bore.
(3) Remove and discard O-ring seal.
INSTALLATION
(1) If necessary, clean and install flow control valve
and spring in pump housing bore.Be sure the hex
nut end of the valve is facing in toward pump.
(2) Install O-ring seal onto fitting (Fig. 10).
(3) Install flow control valve in pump housing and
tighten to 75 Nzm (55 ft. lbs.) torque.
(4) Install pressure hose to valve.
POWER STEERING PUMPÐINITIAL OPERATION
CAUTION: The fluid level should be checked with
engine off to prevent injury from moving compo-
nents. Use only Mopar Power Steering Fluid. Do not
use automatic transmission fluid. Do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicate FULL COLD when the
fluid is at normal temperature 21ÉC to 27ÉC (70ÉF to
80ÉF).
(1) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two (2) minutes.
(2) Start the engine and let run for a few seconds.
Then turn the engine off.
(3) Add fluid if necessary. Repeat the above proce-
dure until the fluid level remains constant after run-
ning the engine.
(4) Raise the front wheels off the ground.
(5) Start the engine. Slowly turn the steering
wheel right and left, lightly contacting the wheel
stops.
(6) Add power steering fluid if necessary.
(7) Lower the vehicle and turn the steering wheel
slowly from lock to lock.
(8) Stop the engine. Check the fluid level and refill
as required.
(9) If the fluid is extremely foamy, allow the vehi-
cle to stand a few minutes and repeat the above pro-
cedure.
Fig. 10 Flow Control Valve Fitting
JSTEERING 19 - 15

CONVERTER STALL TEST
Stall testing involves determining maximum engine
rpm obtainable at full throttle with the rear wheels
locked and the transmission in D range. This test
checks the holding ability of the converter overrun-
ning clutch and both of the transmission clutches.
When stall testing is completed, refer to the Stall
Speed Specifications chart and Stall Speed Diagnosis
guides.
WARNING: NEVER ALLOW ANYONE TO STAND IN
FRONT OF THE VEHICLE DURING A STALL TEST.
ALWAYS BLOCK THE FRONT WHEELS AND APPLY
THE SERVICE AND PARKING BRAKES DURING
THE TEST.
STALL TEST PROCEDURE
(1) Connect tachometer to engine.
(2) Check and adjust transmission fluid level.
(3) Start and run engine until transmission fluid
reaches normal operating temperature.
(4) Block front wheels.
(5) Fully apply service and parking brakes.
(6) Open throttle completely and record maximum
engine rpm registered on tachometer. It will take
from 3 to 10 seconds to reach maximum rpm. How-
ever, once maximum rpm has been achieved,do not
hold wide open throttle for more than 5 sec-
onds.
CAUTION: Stalling the converter causes a rapid in-
crease in fluid temperature. To avoid fluid overheat-
ing, hold wide open throttle for no more than 5
seconds after reaching peak rpm. In addition, if
more than one stall test is required, run the engine
at 1000 rpm with the transmission in Neutral for at
least 20 seconds to cool the fluid.
(7) Stall speeds should be in 1700-2150 rpm range.
CAUTION: If engine exceeds 2150 rpm, release ac-
celerator pedal immediately as transmission clutch
slippage is occurring.
(8) Shift transmission into Neutral. Run engine for
20-30 seconds at 1000 rpm to cool fluid. Then stop
engine, shift transmission into Park and release
brakes.
(9) Refer to Stall Test Diagnosis.
STALL TEST DIAGNOSIS
Stall Speed Too Low
Low stall speeds with a properly tuned engine in-
dicate a torque converter overrunning clutch prob-
lem. The condition should be confirmed by road
testing prior to converter replacement.The converter overrunning clutch is slipping when
stall speeds are 250 to 350 rpm below specified min-
imum.
A converter overrunning clutch failure will result
in sluggish acceleration in all speed ranges. It will
also require greater than normal throttle opening to
maintain cruising speeds.
Stall Speed Too High
If stall speed exceeds 2150 rpm, transmission
clutch slippage is occurring.
Stall Speed Normal But Acceleration Is Sluggish
If stall speeds are within specified range but abnor-
mal throttle opening is required for acceleration, or
to maintain cruise speeds, the converter overrunning
clutch is seized. The torque converter will have to be
replaced.
Converter Noise During Test
A whining noise caused by fluid flow is normal dur-
ing a stall test. However, loud metallic noises indi-
cate a damaged converter. To confirm that noise is
originating from the converter, operate the vehicle at
light throttle in Drive and Neutral on a hoist and lis-
ten for noise from the converter housing.
AIR PRESSURE TEST
Air pressure testing can be used to check clutch
and band operation with the transmission either in
the vehicle, or on the work bench as a final check af-
ter overhaul.
Air pressure testing requires that the oil pan and
valve body be removed from the transmission.
The servo and clutch apply passages are shown in
Figure 8.
Air Test Procedure
(1) Place one or two fingers on the clutch housing
and apply air pressure through front clutch apply
passage (Fig. 8). Piston movement can be felt and a
soft thud heard as the clutch applies.
(2) Place one or two fingers on the clutch housing
and apply air pressure through rear clutch apply
passage (Fig. 8). Piston movement can be felt and a
soft thud heard as the clutch applies.
(3) Apply air pressure to the front servo apply pas-
sage. The servo rod should extend and cause the
band to tighten around the drum. Spring tension
should release the servo when air pressure is re-
moved.
(4) Apply air pressure to the rear servo apply pas-
sage. The servo rod should extend and cause the
band to tighten around the drum. Spring tension
should release the servo when air pressure is re-
moved.
21 - 74 30RH/32RH TRANSMISSION DIAGNOSISJ

CONNECTING COOLER LINES AND FITTINGS
(ALL TYPES)
(1) Wipe cooler line and fitting clean with shop
towel.
(2) Insert cooler line into fitting. Then push line
inward until retainer or insert secures line. A snap or
click sound will be heard when the insert tabs or re-
tainer clip seats behind the cooler line flange.
(3)Pull outward on cooler lines/fittings to
verify they are properly secured.
CAUTION: The wire retainer clips or insert release
tabs secure the cooler lines. If the clips or tabs are
deformed, distorted, or not fully seated, normal
fluid pressure could unseat the lines resulting in
fluid loss and transmission damage. Be very sure
the cooler lines are firmly secured as described in
step (3).
CONVERTER DRAINBACK CHECK VALVE SERVICE
The converter drainback check valve is located in
the cooler outlet (pressure) line near the radiator
lower tank. The valve prevents fluid drainback when
the vehicle is parked for lengthy periods. The valve
check ball is spring loaded and has an opening pres-
sure of approximately 2 psi. Refer to the cooler flow
test procedure for valve testing.
The valve is serviced as an assembly; it is not re-
pairable. Do not clean the valve if restricted, or con-
taminated by sludge, or debris. If the valve fails, or if
a transmission malfunction occurs that generates
sludge and/or clutch particles and metal shavings,
the valve must be replaced.
The valve must be removed whenever the cooler
and lines are reverse flushed. The valve can be flow
tested when necessary. The procedure is exactly the
same as for flow testing a cooler.
If the valve is restricted, installed backwards, or in
the wrong line, it will cause an overheat condition
and possible transmission failure.
CAUTION: The drainback valve is a one-way valve.
As such, it must be properly oriented in terms of
flow direction. In addition, the valve must only beinstalled in the pressure line. Otherwise flow will be
blocked causing overheat and eventual transmis-
sion failure.
TRANSMISSION COOLER FLOW TESTING
The transmission main and auxiliary coolers, plus
the drainback valve, should be flow tested whenever
fluid overheating is noted.
Restricted flow caused by contamination, or a
cooler malfunction, reduces lubrication fluid flow
throughout the transmission. This can result in fluid
overheating, fluid breakdown, bushing wear, shift
problems and component failure.
Normal color of transmission fluid varies from
bright red, to light pink. Fluid overheating is indi-
cated when fluid color ranges from orange-brown to
black, and the fluid smells burned, or contains
sludge.
CAUTION: If a transmission malfunction contami-
nates the fluid with clutch disc and metal particles,
the cooler and lines must be reverse flushed thor-
oughly. Flushing will prevent sludge and particles
from flowing back into the transmission and con-
verter after repair.
Cooler flow is tested by measuring the amount of
fluid pumped through the cooler in a specified time
by the transmission oil pump.The same flow test
procedure is used for the drainback valve, main
cooler, and auxiliary cooler.
Cooler And Drainback Valve Flow Test Procedure
(1) Test flow throughdrainback valveas follows:
(a) Add extra quart of ATF Plus to transmission.
(b) Disconnect pressure line at radiator fitting, or
at drainback valve and position hose or valve end
in one quart test container.
(c) Shift transmission into neutral, run engine at
idle speed for 20 seconds, and note flow from valve.
Use stopwatch to check test time.
(d) Replace drainback valve if flow is less than
one quart in 20 seconds, is intermittent, or does
not flow at all.
(e) Connect pressure hose to radiator fitting and
proceed to cooler flow test.
(2) Test flow throughmain cooleras follows:
(a) Disconnect cooler return (rear) line at trans-
mission and place it in one quart test container.
(b) Add extra quart of fluid to transmission.
(c) Shift transmission into neutral, run engine at
idle speed for 20 seconds, and note flow from valve.
Use stopwatch to check test time.
(d) Replace cooler if fluid flow is less than one
quart in 20 seconds, is intermittent, or does not
flow at all.
Fig. 33 New Style Fitting Insert (On Cooler Line)
J30RH/32RH IN-VEHICLE SERVICE 21 - 113