Initial Inspection and Diagnostic Overview

WARNING: ON VEHICLES EQUIPPED WITH AIR-BAGS, REFER TO AIR BAGS AND SEAT BELTS/AIR BAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

Inspection
Before removing any unit from the starting system for repair or diagnosis, perform the following inspections:
- Battery - Visually inspect the battery for indications of physical damage and loose or corrode cable connections. Determine the state-of-charge and cranking capacity of the battery. Charge or replace the battery, if required.
- Ignition Switch - Visually inspect the ignition switch for indications of physical damage and loose or corroded wire harness connections.
- Clutch Pedal Position Switch - Visually inspect the clutch pedal position switch for indications of physical damage and loose or corroded wire harness connections.
- Park/Neutral Position Switch - Visually inspect the park/neutral position switch for indications of physical damage and loose or corroded wire harness connections.
- Starter Relay - Visually inspect the starter relay for indications of physical damage and loose or corroded wire harness connections.
- Starter - Visually inspect the starter for indications of physical damage and loose or corroded wire harness connections.
- Starter Solenoid - Visually inspect the starter solenoid for indications of physical damage and loose or corroded wire harness connections.
- Wiring - Visually inspect the wire harness for damage. Repair or replace any faulty wiring, as required.

Starter System Diagnosis:

Cold Cranking Test
The battery must be fully-charged and load-tested before proceeding. Refer to Starting and Charging/Battery for more information.

Volts - Amps Tester Connections - Typical:

1. Connect a suitable volt-ampere tester to the battery terminals. Refer to the operating instructions provided with the tester being used.
2. Fully engage the parking brake.
3. If the vehicle is equipped with an automatic transmission, place the gearshift selector lever in the Park position. If the vehicle is equipped with a manual transmission, place the gearshift selector lever in the Neutral position and fully depress the clutch pedal.
4. Verify that all lamps and accessories are turned off.
5. To prevent the engine from starting, unplug the Automatic Shut Down (ASD) relay. The ASD relay is located in the Power Distribution Center (PDC). Refer to the PDC label for relay identification and location.
6. Rotate and hold the ignition switch in the Start position. Note the cranking voltage and current (amperage) draw.
a. If the voltage reads below 9.6 Volts, remove the starter for bench testing. If the starter bench test is OK, refer to Engine for further diagnosis of the engine. If the starter bench test is not OK, replace the faulty starter.
b. If the voltage reads above 9.6 Volts and the current (amperage) draw reads below specifications, see the Feed Circuit Test procedures.
c. If the voltage reads 12.5 Volts or greater and the starter does not turn.
d. If the voltage reads 12.5 Volts or greater and the starter turns very slowly, see the Feed Circuit Test procedures.

NOTE: A cold engine will increase the starter current (amperage) draw reading, and reduce the battery voltage reading.

Feed Circuit Test
The starter feed circuit test (voltage drop method) will determine if there is excessive resistance in the high-amperage circuit. When performing these tests, it is important to remember that the voltage drop is giving an indication of the resistance between the two points at which the voltmeter probes are attached.

Example: When testing the resistance of the battery positive cable, touch the voltmeter leads to the battery positive cable clamp and the cable connector at the starter solenoid. If you probe the battery positive terminal post and the cable connector at the starter solenoid, you are reading the combined voltage drop in the battery positive cable clamp-to-terminal post connection and the battery positive cable.
The following operation will require a voltmeter accurate to 1/10 (0.10) Volt. Before performing the tests, be certain the following procedures are accomplished:
- Battery is fully-charged. Refer to Starting and Charging/Battery for more information.
- Fully engage the parking brake.
- If the vehicle is equipped with an automatic transmission, place the gearshift selector lever in the Park position. If the vehicle is equipped with a manual transmission, place the gearshift selector lever in the Neutral position and fully depress the clutch pedal.
- Unplug the Automatic Show Down (ASD) relay to prevent the engine from starting. The ASD relay is located in the Power Distribution Center (PDC). Refer to the PDC label for ASD relay identification and location.

Test Battery Negative Connective Resistance - Typical:

1. Connect the positive lead of the voltmeter to the battery negative terminal post. Connect the negative lead of the voltmeter to the battery negative cable clamp. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If voltage is detected, correct the poor contact between the cable clamp and the terminal post.

Test Battery Positive Connective Resistance - Typical:

2. Connect the positive lead of the voltmeter to the battery positive terminal post. Connect the negative lead of the voltmeter to the battery positive cable clamp. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If voltage is detected, correct the poor contact between the cable clamp and the terminal post.

Test Battery Positive Connective Resistance - Typical:

3. Connect the voltmeter to measure between the battery positive terminal post and the starter solenoid battery terminal stud. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If the reading is above 0.2 Volt, clean and tighten the battery cable connection at the solenoid. Repeat the test. If the reading is still above 0.2 Volt, replace the faulty battery positive cable.

Test Ground Circuit Resistance - Typical:

4. Connect the voltmeter to measure between the battery negative terminal post and a good clean ground on the engine block. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If the reading is above 0.2 Volt, clean and tighten the battery negative cable attachment on the engine block. Repeat the test. If the reading is still above 0.2 Volt, replace the faulty battery negative cable.

Test Starter Ground - Typical:

5. Connect the positive lead of the voltmeter to the starter housing. Connect the negative lead of the voltmeter to the battery negative terminal post. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If the reading is above 0.2 Volt, correct the poor starter to engine block ground contact. If the resistance tests detect no feed circuit problems, remove the starter and see the Starting and Charging/Starting System/Solenoid Test procedure.

Control Circuit Test
The starter control circuit consists of:
- Battery
- Starter relay
- Starter solenoid
- Ignition switch
- Park/neutral position switch (automatic transmission)
- Clutch pedal position switch (manual transmission)
- Wire harness and connections.
Test procedures for these components should be performed in the order in which they are listed, as follows:

Solenoid Test
Remove the starter as described. Then proceed as follows:
1. Remove the wire from the solenoid field coil terminal.

Continuity Test Between Solenoid Terminal And Field Coil Terminal:

2. Check for continuity between the solenoid terminal and the field coil terminal with a continuity tester. There should be continuity. If OK, go to Step 3. If not OK, replace the faulty starter assembly.

Continuity Test Between Solenoid Terminal And Solenoid Case:

3. Check for continuity between the solenoid terminal and the solenoid case. There should be continuity. If OK, go to Step 4. If not OK, replace the faulty starter assembly.
4. Connect the solenoid field coil wire to the field coil terminal.
5. Install the starter as described.

Relay Test
The starter relay is located in the Power Distribution Center (PDC) in the engine compartment. Refer to the PDC label for starter relay identification and location.
Remove the starter relay from the PDC as described to perform the following tests:
1. A relay in the de-energized position should have continuity between terminals 87A and 30, and no continuity between terminals 87 and 30. If OK, go to Step 2. If not OK, replace the faulty relay.
2. Resistance between terminals 85 and 86 (electromagnet) should be 75 ± 5 Ohms. If OK, go to Step 3. If not OK, replace the faulty relay.

Starter Relay:

3. Connect a battery to terminals 85 and 86. There should now be continuity between terminals 30 and 87, and no continuity between terminals 87A and 30. If OK, see the Relay Circuit Test procedure. If not OK, replace the faulty relay.

Relay Circuit Test
1. The relay common feed terminal cavity (30) is connected to battery voltage and should be hot at all times. If OK, go to Step 2. If not OK, repair the open circuit to the PDC fuse as required.
2. The relay normally closed terminal (87A) is connected to terminal 30 in the de-energized position, but is not used for this application. Go to Step 3.
3. The relay normally open terminal (87) is connected to the common feed terminal (30) in the energized position. This terminal supplies battery voltage to the starter solenoid field coils. There should be continuity between the cavity for relay terminal 87 and the starter solenoid terminal at all times. If OK, go to Step 4. If not OK, repair the open circuit to the starter solenoid as required.
4. The coil battery terminal (86) is connected to the electromagnet in the relay. It is energized when the ignition switch is held in the Start position. On vehicles with a manual transmission, the clutch pedal must be fully depressed for this test. Check for battery voltage at the cavity for relay terminal 86 with the ignition switch in the Start position, and no voltage when the ignition switch is released to the On position. If OK, go to Step 5. If not OK with an automatic transmission, check for an open or short circuit to the ignition switch and repair, if required. If the circuit to the ignition switch is OK, see the Starting and Charging/Starting System/Ignition Switch Test procedure. If not OK with a manual transmission, check the circuit between the relay and the clutch pedal position switch for an open or a short. If the circuit is OK, see the Brakes and Traction Control/Brakes/Anti-lock Brakes/Clutch Pedal Position Switch Test procedure.
5. The coil ground terminal (85) is connected to the electromagnet in the relay On vehicles with an automatic transmission, it is grounded through the park/neutral position switch only when the gearshift selector lever is in the Park or Neutral positions. On vehicles with a manual transmission, it is grounded at all times. Check for continuity to ground at the cavity for relay terminal 85. If not OK with an automatic transmission, check for an open or short circuit to the park/neutral position switch and repair, if required. If the circuit is OK, see the Starting and Charging/Starting System/Neutral Safety Switch/Park/Neutral Position Switch.

Park/Neutral Position Switch Switch Test
For testing of the park/neutral position switch, refer to Neutral Safety Switch.

Ignition Switch Test

WARNING: ON VEHICLES EQUIPPED WITH AIR BAGS, REFER TO AIR BAGS AND SEAT BELTS/AIR BAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIR-BAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

1. Disconnect and isolate the battery negative cable.
2. Remove the steering column shrouds and unplug the ignition switch wire harness connector.
3. With the ignition switch in the On position, check for continuity between the ignition switch fused B(+) circuit terminal and the ignition switch output (start) circuit terminal. There should be no continuity. If OK, go to Step 4. If not OK, replace the faulty switch.
4. With the ignition switch held in the Start position, check for continuity between the ignition switch fused B(+) circuit terminal and the ignition switch output (start) circuit terminal. There should now be continuity. If not OK, replace the faulty switch.