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Checking a No Crank Condition






CHECKING A NO CRANK CONDITION

For a complete wiring diagram, refer to the Wiring Information.






1. MECHANICAL CONDITION

NOTE: Diagnose and repair any Body Control Module (BCM) DTCs before continuing. An inoperative Key FOBIK or SKIS can cause a No Crank Condition.

NOTE: Diagnose and repair any Powertrain Control Module (PCM) and Transmission Control Module (TCM) DTCs before continuing.

NOTE: Verify the battery is fully charged and capable of passing a load test before continuing.

WARNING: Make sure the battery is disconnected, then wait two minutes before proceeding. Failure to do so may result in possible serious or fatal injury.

1. Turn the engine over by hand to make sure the engine is not seized.

Is the engine able to turn over?

Yes

- Go To 2

No

- Repair the mechanical condition preventing the starter motor from cranking.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

2. PARK/NEUTRAL POSITION
1. Place the transmission in PARK for automatic transmissions.
2. Press the clutch pedal in for manual transmissions.
3. With the scan tool, read the Park Neutral Switch Filtered Switch State or Clutch Switch status.

NOTE: With the transmissions in PARK, the scan tool Park Neutral Switch Filtered Switch State should be On.

Does the scan tool Park Neutral Switch Filtered Switch State equal the specified value?

Yes

- Go To 3

No

- Adjust the shift cable or replace the clutch switch or
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

3. EXCESSIVE RESISTANCE IN THE BATTERY CIRCUIT
1. Turn the ignition off.
2. Check the Battery Cables for excessive resistance.

Did either Battery Cable have a voltage drop greater than 0.2 of a Volt?

Yes

- Repair the excessive resistance in the Battery circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 4

4. STARTER RELAY GROUND CIRCUIT OPEN
1. Remove the Starter Relay.
2. Using a 12-volt test light connected to B+, check the Starter Relay ground circuit.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connector to the battery.

Does the test lamp illuminate brightly?

Yes

- Go To 5

No

- Repair the open in the starter relay ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. STARTER RELAY IGNITION RUN/START CIRCUIT OPEN OR SHORTED
1. Have an assistant place the ignition in the CRANK position.
2. Using a 12-volt test light connected to ground, check the Starter Relay Ignition Run/Start circuit with the key in the CRANK position at the relay terminal.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connector to the battery.

Does the test lamp illuminate brightly?

Yes

- Go To 6

No

- Repair the open or short to ground in the Starter Relay Ignition Run/Start circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

6. (T750) STARTER RELAY OUTPUT CIRCUIT CHECK




1. Turn the ignition off.
2. Install the Starter Relay.
3. Disconnect the Starter harness connector.
4. Connect a 12-volt test lamp between the (T750) Starter Relay Output circuit and ground at the starter harness connector.
5. While observing the 12-volt test light, place the ignition in the CRANK position.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connector to the battery.

Does the test lamp illuminate brightly?

Yes

- Replace the Starter.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 7

7. (T750) STARTER RELAY OUTPUT CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Remove the Starter Relay.
3. Measure the resistance between ground and the (T750) Starter Relay Output circuit.

Is the resistance below 100 Ohms?

Yes

- Repair the short to ground in the (T750) Starter Relay Output circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 8

8. (T750) STARTER RELAY OUTPUT CIRCUIT OPEN OR EXCESSIVE RESISTANCE
1. Measure the resistance of the (T750) Starter Relay Output circuit between the Relay and the Starter Solenoid harness connector.

Is the resistance above 5 Ohms?

Yes

- Repair the open or excessive resistance in the (T750) Starter Relay Output circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 9

9. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Starter Relay and PCM.
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Verify that there is good pin to terminal contact in the PCM connectors.
5. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module (PCM). PCM/ECM Reprogramming
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

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