Page 1361 of 5267
P1277-STARTER CONTROL CIRCUIT 2 LOW (TIPM)
For a complete wiring diagramRefer to Section 8W.
Page 1362 of 5267

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 goodtripstoturnofftheMIL.
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. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.(T40) STARTER FEED CIRCUIT SHORTED TO GROUND
Turn the ignition.
Disconnect the Starter Relay.
Disconnect the C9 TIPM harness connector.
Measure the resistance between ground and the (T40) Starter Relay Output circuit in the C9 TIPM harness con-
nector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (T40) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
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 Outputcircuit in the Starter Relay harness
connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (T750) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
Page 1363 of 5267
4.TIPM OPERATION
Reconnect the C9 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.
Does the test light illuminate?
Ye s>>
Go To 5
No>>
Replace the TIPM is accordance with the Service information
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
5.STARTER RELAY
Turn the ignition off.
Install the Starter Relay.
NOTE: The Stater Solenoid harness connector must still be disconnected atthis time.
Crank the engine.
Using a 12-volt test light connected ground, probe the (T750) Stater RelayOutput circuit in the Starter Solenoid
harness connector.
Does the test light illuminate?
Ye s>>
Replace the Starter.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace the Starter Relay.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 1364 of 5267
P1278-STARTER CONTROL CIRCUIT 2 HIGH (TIPM)
For a complete wiring diagramRefer to Section 8W.
Page 1365 of 5267

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 goodtripstoturnofftheMIL.
Possible Causes
(T40) STARTER RELAY OUTPUT CIRCUIT SHORTED TO BATTERY VOLTAGE
(T750) STARTER RELAY OUTPUT CIRCUIT SHORTED TO BATTERY VOLTAGE
STARTER RELAY
STARTER
TIPM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.(T40) STARTER FEED CIRCUIT SHORTED TO BATTERY VOLTAGE
Turn the ignition off.
Disconnect the Starter Relay.
Disconnect the C9 TIPM harness connector.
Turn the ignition on.
Measure the voltage of the (T40) Starter Relay Output circuit in the C9 TIPMharness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to voltage in the (T40) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3
3.(T750) STARTER RELAY OUTPUT CIRCUIT SHORTED TO BATTERY VOLTAGE
Disconnect the Starter Solenoid connector.
Measure the voltage of the (T750) Starter Relay Output circuit in the Starter Relay harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to voltage in the (T750) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
Page 1366 of 5267
4.STARTER
Reconnect the Starter Solenoid harness connector.
Using a 12-volt test light connected ground, probe the (T750) Stater RelayOutput circuit in the Starter Relay har-
ness connector.
Crank the engine.
Does the test light illuminate?
Ye s>>
Replace the Starter in accordance with the Service information
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
5.STARTER RELAY INTERNAL SHORT
Install a substitute relay inplaceoftheStarterRelay.
Reconnect the C9 TIPM harness connector.
Crank the engine.
With a scan tool, read DTCs.
Does the DTC reset?
Ye s>>
Replace the TIPM in accordance with the Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace the Starter Relay.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 1367 of 5267
P1279-STARTER CONTROL CIRCUIT 2 OPEN (TIPM)
For a complete wiring diagramRefer to Section 8W.
Page 1368 of 5267

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 goodtripstoturnofftheMIL.
Possible Causes
(T40) STARTER RELAY OUTPUT CIRCUIT OPEN
(T750) STARTER RELAY OUTPUT CIRCUIT OPEN
STARTER RELAY
STARTER
TIPM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.(T40) STARTER FEED CIRCUIT OPEN
Turn the ignition.
Disconnect the Starter Relay.
Disconnect the C9 TIPM harness connector.
Measure the resistance of the (T40) Starter Relay Output circuit between the C9 TIPM harness connector and the
Starter Relay harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 3
No>>
Repair the open in the (T40) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
3.(T750) STARTER RELAY OUTPUT CIRCUIT OPEN
Disconnect the Starter Solenoid connector.
Measure the resistance of the (T750) Starter Relay Output circuit betweenthe Starter Solenoid harness connector
and the Starter Relay harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 4
No>>
Repair the open in the (T750) Starter Relay Output circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)