IGNITION OFF DRAW (IOD)
GENERAL INFORMATION
A normal electrical system will draw from 5 to 30
milliamperes from the battery. This is with the ignition
in the OFF position, and all non-ignition controlled cir-
cuits in proper working order. The amount of IOD will
depend on body model and electrical components. A ve-
hicle that has not been operated for an extended period
of approximately 20 days may discharge the battery to
an inadequate level. In this case, the Main Fusible Link
Connector should be disconnected. The Main Fusible
Link connector is located rearward of the battery on the
engine wiring harness (Fig. 19).
If the IOD is over 30 milliamperes, the defect must
be found and corrected before condemning the bat-
tery. Usually, the battery can be charged and re-
turned to service (Fig. 16).
IGNITION OFF DRAW (IOD) TESTS
VEHICLES WITHOUT ELECTRONIC AUTOMATIC TRANSMISSION/LOAD LEVELINGSUSPENSION OR ALARM SYSTEMS
Testing for HIGHER AMPERAGE IOD must be
performed first to prevent damage to most milliamp
meters. A standard 12 volt test light and a milliamp meter
that is equipped with two leads will be used for the
following tests. The milliamp meter should be able to
handle up to two amps.
(1) Verify that all electrical accessories are OFF.
Turn off all lights, close trunk lid, close glove box door,
turn off sun visor vanity lights, close all doors and re- move ignition key. Allow the Illuminated Entry System
if equipped to time out in approximately 30 seconds.
(2) Verify the engine compartment lamp bulb is
working by opening/closing hood. Remove the lamp. (3) Disconnect negative battery cable (Fig. 15).
(4) Connect a typical 12 volt test light between the
negative cable clamp and the negative battery post (Fig.
19). The test light may be brightly lit for up to three
minutes or may not be lit at all. This depending on the
body model or electronic components on the vehicle. (a) The term brightly used throughout the follow-
ing tests. This implies the brightness of the test light
will be the same as if it were connected across the
battery posts. This would be with a fully charged bat-
tery.
(b) The test light or the milliamp meter MUST
be positively connected to the battery post and the
battery cable during all IOD testing. (c) Do not allow the test light or the milliamp
meter to become disconnected during any of the
IOD tests. If this happens, the electronic timer
functions will be started and all IOD tests must be
repeated from the beginning. Clamp the test light
at both ends to prevent accidental disconnection.
(d) After three minutes time has elapsed, the test
light should turn OFF or be dimly lit depending on
the electronic components on the vehicle. If the test
light remains BRIGHTLY lit, do not disconnect test
light. Disconnect each fuse or circuit breaker until
test light is either OFF or DIMLY lit. Refer to the
Front Wheel Drive Car Wiring Diagrams Service
Manual. This will eliminate higher amperage IOD. It
is now safe to install the milliamp meter without
damage to the meter to check for low amperage IOD.
(e) Possible sources of high IOD are usually ve-
hicle lamps trunk lamp, glove compartment, lug-
gage compartment, etc.. (f) If test light is still brightly lit after discon-
necting each fuse and circuit breaker, disconnect
the wiring harness from the generator. Refer to
Generator Testing. Do not disconnect test light.
CAUTION: This last test has higher amperage IOD and
must be performed before going on with low amper-
age IOD tests. The higher amperage IOD must be elim-
inated before hooking up milliamp meter to check for
low amperage IOD. If higher amperage IOD has not
been eliminated, milliamp meter may be damaged.
Most milliamp meters will not handle over one or two
amps. Do not hook up meter if test light is glowing
brightly. Refer to maximum amperage specifications
and instructions supplied with milliamp meter.
After higher amperage IOD has been corrected, low
amperage IOD may be checked. The MAXIMUM IOD=
30 MILLIAMPERES.
Fig. 19 IOD Test
Ä BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 9
FAILURE TO START TEST
This no-start test checks the camshaft position sen-
sor and crankshaft position sensor. The powertrain control module (PCM) supplies 8.0
volts to the camshaft position sensor and crankshaft
position sensor through one circuit. If the 8.0-volt
supply circuit shorts to ground, neither sensor will
produce a signal (output voltage to the PCM). When the ignition key is turned and left in the On
position , the PCM automatically energizes the auto shutdown (ASD) relay. However, the PCM de-energizes
the relay within one second because it has not received
a crankshaft position sensor signal indicating engine
rotation.
During cranking, the ASD relay will not energize
until the PCM receives a crankshaft signal. Secondly,
the ASD relay remains energized only if the PCM
senses a camshaft position sensor signal immediately
after detecting the crankshaft position sensor signal. (1) Check battery voltage. Voltage should approxi-
mately 12.66 volts or higher to perform failure to start
test. (2) Disconnect the harness connector from the coil
pack (Fig. 2). (3) Connect a test light to the B+ (battery voltage)
terminal of the coil electrical connector and ground.
The wire for the B+ terminal is dark green with a black
tracer. (4) Turn the ignition key to the ON position.The
test light should flash On and then Off. Do not turn
the Key to off position, leave it in the On position .
(a) If the test light flashes momentarily, the PCM
grounded the auto shutdown (ASD) relay. Proceed to
step 5. (b) If the test light did not flash, the ASD relay did
not energize. The cause is either the relay or one of
the relay circuits. Use the DRBII scan tool to test the
ASD relay and circuits. Refer to the appropriate
Powertrain Diagnostics Procedure Manual. Refer to
the wiring diagrams section for circuit information.
(5) Crank the engine. If the key was placed in the off
position after step 4, place the key in the On position
before cranking. Wait for the test light to flash once,
then crank the engine. (a) If the test light momentarily flashes during
cranking, the PCM is not receiving a camshaft posi-
tion sensor signal. Use the DRBII scan tool to test the
camshaft position sensor and sensor circuits. Refer to
the appropriate Powertrain Diagnostics Procedure
Manual. Refer to the wiring diagrams section for
circuit information. (b) If the test light did not flash during cranking,
unplug the camshaft position sensor connector. Turn
the ignition key to the off position. Turn the key to
the On position, wait for the test light to momen-
tarily flash once, then crank the engine. If the test
light momentarily flashes, the camshaft position
sensor is shorted and must be replaced. If the light
did not flash, the cause of the no-start is in either the
crankshaft position sensor/camshaft position sensor
8.0-volt supply circuit, or the crankshaft position
sensor 5-volt output or ground circuits. Use the
DRBII scan tool to test the crankshaft position sen-
sor and the sensor circuits.
Fig. 6 Ignition Coil Electrical Connection
Fig. 7 Ignition Coil Terminal Identification
Fig. 8 Checking Ignition Coil Secondary Resistance
Ä IGNITION SYSTEMS 8D - 37
Refer to the appropriate Powertrain Diagnostics Pro-
cedure Manual. Refer to the wiring diagrams section
for circuit information.
COOLANT TEMPERATURE SENSOR TEST
(1) With key off, disconnect wire connector from
coolant temperature sensor (Fig. 9).
(2) Connect one lead of ohmmeter to one terminal of
coolant temperature sensor. (3) Connect the other lead of ohmmeter to remaining
terminal of coolant temperature sensor. The ohmmeter
should read as follows;
² Engine/Sensor hot at normal operating temperature
around 200ÉF should read approximately 700 to 1,000
ohms.
² Engine/Sensor at room temperature around 70ÉF,
ohmmeter should read approximately 7,000 to 13,000
ohms. To test the coolant temperature sensor circuits,
refer to the DRBII scan tool and the appropriate
Powertrain Diagnostic Service manual.
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
TEST
Refer to the appropriate Powertrain Diagnostic Pro-
cedure manual.
CRANKSHAFT POSITION SENSOR AND CAMSHAFT
POSITION SENSOR TESTS
Refer to the appropriate Powertrain Diagnostic Pro-
cedure manual.
Fig. 9 Coolant Temperature Sensor Test
8D - 38 IGNITION SYSTEMS Ä
(2) With the ignition key ON, check for ignition
voltage at ignition pin of gauge. Check for ground at
ground pin of gauge. Refer to the individual gauge
circuit test for proper pin. (a) If voltage at pin, replace gauge.
(b) If no voltage or ground at gauge pins, check
for ignition voltage and ground at cluster harness
connectors. (c) If no voltage or ground, repair as necessary.
Refer to 8W, Wiring Diagrams. (d) If there is voltage or ground, check cluster for
distorted terminals. If terminals are OK, replace
printed circuit board.
Fig. 19 Voltmeter PinsÐWith Tachometer
Fig. 20 Voltmeter PinsÐWithout Tachometer
Fig. 21 Temperature Gauge PinsÐWith Tachometer
Fig. 22 Temperature Gauge PinsÐWithout Tachometer
Fig. 23 Oil Pressure Gauge PinsÐWith Tachometer
8E - 8 INSTRUMENT PANEL AND GAUGES Ä
or bind the transmission range indicator guide tube
and position guide tube in original location.(5) Adjust with tool if necessary to center pointer
on N (Neutral) and check in other gears (Fig. 14). (6) Install upper and lower steering column cover.
(7) Install the rear window defogger bezel and ra-
dio bezel. (8) Install cluster bezel.
(9) Reconnect battery.
REMOVALÐCLUSTER WITHOUT TRANSMISSION RANGE
INDICATOR FROM STEERING COLUMN
(1) Remove cluster bezel (Fig. 10).
(2) Remove four screws attaching cluster to base
panel. (3) Pull cluster rearward carefully, reach behind
and disconnect the two harness connectors. (4) Carefully rotate cluster and remove the two
transmission range indicator screws. (5) Remove cluster assembly.
(6) For installation reverse above procedures. (a) Do not kink guide tube when installing clus-
ter. (b) Replace guide tube behind fuse block.
GAUGES
It is not necessary to remove instrument cluster
from vehicle for gauge replacement. When removing
gauge assemblies from cluster, gauge must be pulled
straight out, not twisted, or damage to gauge pins
may result.
MULTIPLE GAUGE MALFUNCTION
If all the instrument cluster gauges appear to be
malfunctioning, remove the cluster assembly.
² Check for good pin contact
² Check for ignition voltage between the IGN cavity
D and ground.
² If there is ignition voltage
² Check for continuity between the wire harness
ground cavity G and ground.
² If there is continuity, replace the print circuit
board (Fig. 16).
GAUGE INOPERATIVE (FIG. 17 THROUGH 20)
(1) Remove gauge in question.
(2) With the ignition key ON, check for ignition
voltage at ignition pin of gauge. Check for ground at
ground pin of gauge. Refer to the individual gauge
circuit test for proper pin. (a) If no voltage or ground at gauge pins. Check
cavity D red cluster connector for ignition voltage
or cavity G for ground. (b) If no voltage or ground, repair as necessary.
Refer to 8W, Wiring Diagrams.
Fig. 15 Cluster With Mask and Lens Removed
Fig. 14 Transmission Range Indicator Step 4
8E - 28 INSTRUMENT PANEL AND GAUGES Ä
(4) Remove six screws holding the cluster mask
and lens assembly. (5) Pull cluster mask and lens rearward to remove
(Fig. 5 and 6).
(6) For installation reverse above procedures.
CLUSTER ASSEMBLY REMOVAL
(1) Disconnect battery to assure no Air Bag Sys-
tem fault codes are stored. (2) Remove switch pod assembly.
(3) Unscrew tilt column lever if equipped.
(4) Remove steering column trim cover.
(5) Remove attaching screws on cluster and pull
cluster rearward. (6) Tilt cluster to disconnect wiring connections
and turbo gauge hose if equipped, then remove clus-
ter. (7) For installation reverse above procedures.
GAUGES
MULTIPLE GAUGE INOPERATIVE
Volt, speedometer, tachometer and other gauges
appear to malfunction: (1) Remove cluster
(2) Check for ignition voltage at cavity 9 of the red
cluster connector and ground. If no voltage, repair as
necessary (Fig. 7).
(3) Check for ground continuity between cavity 14
of the red cluster connector and ground. If no ground,
repair as necessary. (4) If OK and pins or connectors are not distorted,
replace printed circuit board. (5) Install cluster.
GAUGE CALIBRATION/INOPERATIVE
(1) Remove gauge in question (Fig. 8 through 11).
(2) With the ignition key ON, check for ignition
voltage at ignition pin of gauge and ground. Check
ground pin of gauge for continuity to ground. (a) If no voltage or ground, check at cluster red
connector pin 9 for ignition voltage and pin 14 for
ground. (b) If no voltage or ground, repair as necessary.
Refer to 8W, Wiring Diagrams. (c) If there is voltage or ground, check cluster for
distorted terminals. If terminals are OK, replace
printed circuit board.
Fig. 5 Cluster Mask and Lens
Fig. 6 Cluster with Mask Removed
Fig. 7 Conventional Cluster Connectors
8E - 44 INSTRUMENT PANEL AND GAUGES Ä
(5) Reconnect battery.
GAUGES
CAUTION: During the removal and installation
watch overlays are not damage.
It is not necessary to remove instrument cluster
from vehicle for gauge replacement. When removing gauge assemblies from cluster,
gauge must be pulled straight out, not twisted, or
damage to gauge pins may result.
MULTIPLE GAUGE INOPERATIVE
Volt, speedometer, tachometer and other gauges
appear to malfunction. Also check warning indicator
lamps: (1) Remove cluster
(2) Check for ignition voltage at pin E of the red
connector. If no voltage, repair as necessary (Fig. 8). (3) Check for ground continuity between pin C of
the gray connector. If no ground, repair as necessary. (4) If voltage and ground OK and pins or connec-
tors are not distorted, replace printed circuit board. (5) Install cluster.
SINGLE GAUGE INOPERATIVE (FIG. 9 AND10)
(1) Remove gauge in question. (2) With the ignition key ON, check for ignition
voltage at ignition pin of gauge. Check for ground at
ground pin of gauge. (a) If no voltage or ground, remove cluster and
check pin E red connector for ignition voltage or
pin C gray connector for ground (Fig. 8). (b) If no voltage or ground, repair as necessary.
Refer to 8W, Wiring Diagrams. (c) If there is voltage or ground, check cluster for
distorted terminals. If terminals are OK, replace
printed circuit board.
(3) When testing the temperature gauge, allow the
engine to run until the vehicle reaches a normal op-
erating temperature. Turn ignition OFF and remove
gauge from cluster.
² When checking the temperature and oil pressure
gauges, it is important to have the same engine tem-
perature and engine speed when noting gauge posi-
tion.
² The time between gauge position reading and
sending unit measuring should be kept to a mini-
mum.
² When testing oil pressure gauge, engine needs to
be running. (a) Measure and record the resistance between
sending unit pin and ground pin of the gauge in
question. Refer to Gauge Calibration.
Fig. 7 Upper Instrument Panel Components
Ä INSTRUMENT PANEL AND GAUGES 8E - 61
Electronic vehicle speed control may be tested us-
ing two different methods. One involves use of a
DRB II. If this test method is desired, refer to the
Powertrain Diagnostic Test Procedures for charging
and vehicle speed control manual. The other test method uses a volt/ohm meter and is
described in the following tests. If any information is needed concerning wiring, re-
fer to Group 8W, Wiring Diagrams.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals, or seals. If
these components are damaged, intermittent or
complete system failure may occur.
SERVO ELECTRICAL TESTS
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAG, SEE GROUP 8M, RESTRAINT SYSTEMS FOR
AIRBAG, STEERING WHEEL OR COLUMN RE-
MOVAL PROCEDURES.
(1) Turn ignition switch to the ON position. With
the vehicle speed control switch in the ON position,
set up a voltmeter to read battery voltage and con-
nect the negative lead to a good chassis ground. (2) Disconnect the four-way connector going to the
servo (Fig. 12). Test pin 2 of the main harness four-
way connector for battery voltage. If not OK go to
step 3. If voltage is OK go to step 4. (3) Perform the following tests.(a) Disconnect the six-way connector at the stop
lamp switch and test pin 1 of the main harness for
battery voltage. If voltage is OK perform the stop
lamp switch test. (b) If the stop lamp switch tests OK; repair wire
between the servo and the stop lamp switch. (c) If no voltage at pin 1 at the 6-way stop lamp
connector, remove the vehicle speed control switch
and disconnect the four-way connector. Test pin 1
of main harness for battery voltage. (d) If voltage is OK perform the vehicle speed
control switch test. (e) If vehicle speed control switch is OK, test
continuity across the clockspring. (f) If clockspring OK, repair as required, wire be-
tween stop lamp switch and clockspring. (g) If no voltage at pin 1 of the 4-way vehicle
speed control switch connector.
² Test for battery voltage between the ignition and
the fuse
² If voltage OK, check fuse
² If fuse OK, repair wire between fuse and clock-
spring
Fig. 7 Vehicle Speed ControlÐAC & AY Bodies with 3.0L
8H - 4 VEHICLE SPEED CONTROL Ä