7B-16 AUTOMATIC TRANSMISSION (4 A/T)
2. DIAGNOSTIC TROUBLE CODE (DTC) CHECK, RECORD AND CLEARANCE
To check DTC, refer to “DTC CHECK” in this section. When a DTC exists, it means existence of a malfunction in
the system represented by that code but whether it still exists (current) or it occurred in the past and has gone
(history) is unknown. To know it, clear this DTC once (Refer to “DTC CLEARANCE” in this section.), perform
test drive and/or “TROUBLE SYMPTOM CONFIRMATION” in this section and then check DTC again as
described in “DTC CHECK”. Attempt to diagnose the trouble based on the DTC recorded in this step only or fail-
ure to clear the DTC in this step may mislead the diagnosis or make diagnosing difficult. Even after checking the
DTC with the SUZUKI scan tool, diagnosis should be performed according to this flow chart to check TCM for
proper self-diagnosis function.
3 and 4. VISUAL INSPECTION
As a preliminary step, perform visual check of the following items that support proper function of the automatic
transmission.
5.TROUBLE SYMPTOM CONFIRMATION
Check if what the customer claimed in “CUSTOMER COMPLAINT ANALYSIS” is actually found in the vehicle
and if that symptom is found, whether it is identified as a failure. (This step should be shared with the customer
if possible.)
When the symptom is not actually found, possibility is :
The symptom occurs under certain conditions.
----- Retry with the vehicle under different conditions.
The trouble occurred only temporarily and normal operation has been restored.
----- Perform “DTC CHECK” and if the diagnostic trouble code is indicated, inspect according to the flow
table for that DTC.
6 and 7. RECHECKING AND RECORD OF DTC
Refer to “DTC CHECK” in this section.INSPECTION ITEM REFERRING SECTION
Engine oil ----- level, leakage Section 0B
Engine coolant ----- level, leakage Section 0B
A/T fluid ----- level, leakage, color Section 0B
Battery ----- fluid level, corrosion of terminal
A/T fluid hoses ----- disconnection, looseness, deterioration
Connectors of electric wire harness ----- disconnection, friction Section 8
Fuses ----- burning Section 8
Parts ----- installation, bolt ----- looseness
Parts ----- deformation
Other parts that can be checked visually
Also add following items at engine start.
Indicator, warning lights in combination meter ----- ON
(indicating abnormality in system) or OFFSection 8C
Other parts that can be checked visually
AUTOMATIC TRANSMISSION (4 A/T) 7B-17
8. AUTOMATIC TRANSMISSION BASIC CHECK AND TROUBLE DIAGNOSIS TABLE
Perform basic automatic transmission check according to the list below first. When the end of the list has been
reached, check the part of system suspected as a possible cause referring to “TROUBLE DIAGNOSIS TABLE”
and based on symptoms appearing on vehicle (symptoms obtained through steps of customer complaint analy-
sis, trouble symptom confirmation and/or A/T basic check) and repair or replace faulty parts, if any.
AUTOMATIC TRANSMISSION BASIC CHECK LIST
1) Power Supply Voltage Check
Check that the battery voltage is within 10 – 14 V at engine stop.
2) A/T Fluid Check
Check A/T fluid level and quality.
3) STALL TEST
Perform stall test. Refer to “STALL TEST” in this section for details.
4) LINE PRESSURE TEST
Perform line pressure test. Refer to “LINE PRESSURE TEST” in this section.
5) ROAD TEST
Perform road test to understand correctly the trouble area.
6) Electrical Harness and Coupler Check
Check the connection of the harness coupler. Check for the loose connection of the harness, loose connec-
tion of the terminals.
9. DIAGNOSTIC TROUBLE CODE FLOW TABLE
Based on the DTC indicated in STEP 6 and STEP 7 and referring to “DTC CHECK”, locate the cause of the
trouble, namely in a sensor, switch, wire harness, connector, actuator, TCM or other part and repair or replace
faulty parts.
10. CHECK FOR INTERMITTENT PROBLEM
Check parts where an intermittent trouble is easy to occur (e.g. wire harness, connector, etc.), referring to
“INTERMITTENT AND POOR CONNECTION” in Section 0A and related circuit of DTC recorded in Step 2.
11. FINAL CONFIRMATION TEST
Confirm that the problem symptom has gone and the automatic transmission is free from any abnormal condi-
tions. If what has been repaired is related to the malfunction DTC, clear the DTC once and perform test driving
and confirm that a normal code is indicated.
7B-20 AUTOMATIC TRANSMISSION (4 A/T)
STALL TEST
This test is to check overall performance of automatic transmis-
sion and engine by measuring stall speed at “D” and “R” ranges.
Be sure to perform this test only when transmission fluid is at nor-
mal operating temperature and its level is between FULL and
LOW marks.
1) Apply parking brake and block wheels.
2) Install tachometer.
3) Start engine with select lever shifted to “P”.
4) Depress brake pedal fully.
5) Shift select lever to “D” and depress accelerator pedal fully
while watching tachometer. Read engine rpm quickly when it
has become constant (stall speed).
6) Release accelerator pedal immediately after stall speed is
checked.
7) In the same way, check stall speed in “R” range.
8) Stall speed should be within following specification.
Stall speed
: 2,750 – 3,150 r/min CAUTION:
Do not run engine at stall more than 5 seconds contin-
uously, for fluid temperature may rise excessively
high.
After performing stall test, be sure to leave engine run-
ning at idle for longer than 30 seconds before another
stall test.
Test result Possible cause
Lower than
standard levelLack of engine output
Defective torque converter
Higher than
standard level
in “D” rangeLow line pressure
Malfunctioning 1st & 2nd brake
Malfunctioning rear clutch
Malfunctioning stator one-way clutch
Higher than
standard level
in “R” rangeLow line pressure
Malfunctioning rear clutch
Malfunctioning reverse brake
Malfunctioning stator one-way clutch
Malfunctioning direct clutch
AUTOMATIC TRANSMISSION (4 A/T) 7B-21
TIME LAG TEST
This test is to check conditions of clutch, reverse brake and fluid
pressure. “Time lag” means time elapsed since select lever is
shifted with engine idling till shock is felt.
1) With chocks placed in front and behind front and rear wheels
respectively, depress brake pedal.
2) Start engine.
3) With stop watch ready, shift select lever from “N” to “D”
range and measure time from that moment till shock is felt.
4) Similarly measure time lag by shifting select lever from “N” to
“R” range.
Specification for time lag
“N”
→
→ → → “D” : Less than 1.0 sec.
“N”
→
→→ → “R” : Less than 1.2 sec.
NOTE:
Make sure that selector cable is properly adjusted.
When repeating this test, be sure to wait at least
minute after select lever is shifted back to “N” range.
Engine should be warmed up fully for this test.
Test result Possible cause
When “N” →
“D”
time lag exceeds specification.Low line pressure
Worn rear clutch
Worn 1st & 2nd brake
When “N” →
“R”
time lag exceeds specification.Low line pressure
Worn rear clutch
Worn direct clutch
Worn reverse brake
7B-22 AUTOMATIC TRANSMISSION (4 A/T)
LINE PRESSURE TEST
Purpose of this test is to check operating conditions of each part
by measuring fluid pressure in fluid pressure line.
Line pressure test requires following conditions.
Automatic fluid is at normal operating temperature (70 –
80°C /158 – 176°F).
Fluid is filled to proper level (between FULL and LOW on
dipstick).
1) Apply parking brake securely and place chocks against
wheels.
2) Remove fluid pressure check hole plug bolt.
3) Attach oil pressure gauge to fluid pressure check hole in
transmission case.
Special tool
(A) : 09925-37811-001
4) Depress foot brake fully, run engine at idle and stall then check fluid pressure in “D” or “R” range.
Line pressureCAUTION:
After attaching oil pressure gauge, check that no fluid
leakage exists.
(A)
CAUTION:
Do not continue running engine at stall speed longer than 5 seconds.
“D” range “R” range
At idle speed
7.6 – 9.2 kg/cm
2
108.1 – 130.8 psi14.1 – 17.3 kg/cm
2
200.6 – 246.0 psi
At stall speed
7.9 – 9.5 kg/cm
2
112.4 – 135.0 psi14.4 – 17.6 kg/cm
2
204.8 – 250.2 psi
Test result Possible cause
Line pressure higher than stan-
dard level in each rangeMalfunctioning regulator valve
Line pressure lower than standard
level in each rangMalfunctioning regulator valve
Defective oil pump
Line pressure lower than standard
level only in “D” rangeFluid leakage from “D” range pressure circuit
Fluid leakage from 1st & 2nd brake
Fluid leakage from rear clutch
Line pressure lower than standard
level only in “R” rangeFluid leakage from “R” range pressure circuit
Fluid leakage from rear clutch
Fluid leakage from direct clutch
Fluid leakage from reverse brake
AUTOMATIC TRANSMISSION (4 A/T) 7B-37
DTC P0741 (DTC NO.29) TCC (LOCK-UP) SOLENOID PERFORMANCE OR STUCK OFF
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAG-
NOSTIC FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE”.
2 Check TCC (lock-up) solenoid referring to
“SHIFT SOLENOID VALVES” in this section.
Is it in good condition?Go to Step 3. Replace TCC (lock-up)
solenoid.
3 Check valve body for fluid passage clog, or
lock-up control valve, secondary regulator valve
or signal valve stuck, referring to “TRANSMIS-
SION UNIT REPAIR OVERHAUL” in this sec-
tion.
Are they in good condition?Go to Step 4. Faulty valve body.
4 Substitute a known-good torque converter and
recheck.
Is it OK?Torque converter mal-
function.Overhaul and repair auto-
matic transmission.
DTC DETECTING CONDITION
Difference between turbine rev. and engine rev. too close even though TCM ordered to turn OFF lock-up.
Difference between turbine rev. and engine rev. too wide even though TCM ordered to turn ON lock-up.
AUTOMATIC TRANSMISSION (4 A/T) 7B-47
DTC P0710 (DTC No.36/38) TRANSMISSION TEMPERATURE SENSOR CIRCUIT MALFUNC-
TION
1. Transmission temperature sensor 3. TCM
2. Coupler 4. TCM coupler (viewed from harness side)
DTC DETECTING CONDITION
A/T fluid temperature signal input voltage too low.
A/T fluid temperature signal input voltage does not go down although standard value of engine rev. signal
input.
Step Action Yes No
1 1) Turn ignition switch OFF and disconnect
sensor wire harness coupler.
2) Measure resistance between “BLU/RED”
wire and “GRY/RED” wire terminal of sen-
sor side coupler.
Is it infinity or 0 Ω
?Faulty transmission tem-
perature sensor.
Replace transmission
temperature sensor.Go to Step 2.
2 Is DTC No.36? Go to Step 4. Go to Step 3.
3 Is DTC No.38? Go to Step 5. Go to Step 6.
(When DTC is P0710.)
4 1) Turn ignition switch OFF and connect sen-
sor wire harness coupler.
2) Disconnect TCM couplers.
3) Measure the resistance between terminal
“C44-3” and “C44-16” of disconnected har-
ness side coupler.
Is it about 0 Ω
?“BLU/RED” and “GRY/
RED” wire shorted each
other.Substitute a known-good
TCM and recheck.
AUTOMATIC TRANSMISSION (4 A/T) 7B-51
DTC P1709 (DTC NO.51) ENGINE COOLANT TEMPERATURE/BAROMETRIC PRESSURE
SIGNAL CIRCUIT
1. ECM 3. TCM coupler (viewed from harness side)
2. TCM 4. ECM coupler (viewed from harness side)
DTC DETECTING CONDITION
Engine coolant temperature/barometric pressure signal voltage too low although A/T fluid temperature is
normal operating temperature and engine rev. is standard.
Step Action Yes No
1 Check DTC referring to “ENGINE DIAGNOSIS”
in Section 6.
Is any DTC detected?Inspect and repair refer-
ring to DTC flow table in
Section 6.Go to Step 2.
2 1) Turn ignition switch OFF and disconnect
TCM and ECM couplers.
2) Measure resistance between terminal “C44-
18” of disconnected harness side TCM cou-
pler and body ground.
Is it infinity?Go to Step 3.“WHT/BLK” wire shorted
to ground.
3 1) Turn ignition switch OFF and connect TCM
couplers.
2) Turn ignition switch ON and check voltage
between terminal “C44-18” and body
ground.
Is it 0V?Substitute a known-good
TCM and recheck.Substitute a know-good
ECM and recheck.