P1277

P1277-STARTER CONTROL CIRCUIT 2 LOW (TIPM)

P1277-Starter Control Circuit 2 Low (TIPM):

WHEN MONITORED
With the ignition on. Battery voltage greater than 10.4 volts and the ASD sense switch is on.

SET CONDITION
Actual Starter state is not equal to desired state. One Trip Fault. Three good trips to turn off the MIL.

POSSIBLE CAUSES
- (T40) Starter relay output circuit shorted to ground
- (T750) Starter relay output circuit shorted to ground
- Starter relay
- Starter
- TIPM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. ACTIVE DTC

Ignition on, engine not running.
With a scan tool, read DTCs.

Q: Is the DTC active at this time?

YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. (T40) STARTER FEED CIRCUIT SHORTED TO GROUND

Turn the ignition.
Disconnect the Starter Relay.
Disconnect the C10 TIPM harness connector.
Measure the resistance between ground and the (T40) Starter Relay Output circuit in the C10 TIPM harness connector.

Q: Is the resistance below 100 ohms?

YES: Repair the short to ground in the (T40) Starter Relay Output circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 3

3. (T750) STARTER RELAY OUTPUT CIRCUIT SHORTED TO GROUND

Disconnect the Starter Solenoid connector.
Measure the resistance between ground and the (T750) Starter Relay Output circuit in the Starter Relay harness connector.

Q: 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 4

4. TIPM OPERATION

Reconnect the C10 TIPM harness connector.
Using a 12-volt test light connected ground, probe the (T40) Stater Relay Output circuit in the Starter Relay harness connector.
Crank the engine.

Q: Does the test light illuminate?

YES: Go To 5
NO: Replace the TIPM. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

5. STARTER RELAY

Turn the ignition off.
Install the Starter Relay.

NOTE: The Stater Solenoid harness connector must still be disconnected at this time.

Crank the engine.
Using a 12-volt test light connected ground, probe the (T750) Stater Relay Output circuit in the Starter Solenoid harness connector.

Q: Does the test light illuminate?

YES: Replace the Starter. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Replace the Starter Relay. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test