B3027

CIRCUIT DESCRIPTION
When the key is turned to the crank position, power is supplied to the starter relay terminal 85. After receiving the proper theft deterrent signal from the body control module (BCM), the powertrain interface module (PIM), will supply a ground signal to the starter relay, terminal 86. This will energize the starter relay and allow the starter motor to operate. If there is a problem with the starter relay coil (shorted internally) or the starter relay control circuit (shorted to voltage) that is allowing 12 volts on the starter relay control circuit, this will cause excessive current flow through the PIM causing DTC B3027 to set.

CONDITIONS FOR RUNNING THE DTC
- The ignition switch is in the crank position.
- The ignition voltage is between 5-17 volts.

CONDITIONS FOR SETTING THE DTC
The PIM detects excessive current through the starter relay control circuit.

ACTION TAKEN WHEN THE DTC SETS
- The PIM will shut down the starter relay control circuit.
- The powertrain control module (PCM) will not illuminate the malfunction indicator lamp (MIL).

CONDITIONS FOR CLEARING THE DTC
- A Last Test Failed (current DTC) clears, after the ignition has been cycled and the PIM no longer detects excessive current flow through the starter relay circuit.
- The DTC can be cleared by using the scan tool Clear DTC Information function.

DIAGNOSTIC AIDS
The following may cause an intermittent condition:
- Incorrectly routed harness
- Rubbed through wire insulation
- Broken wire inside the insulation

TEST DESCRIPTION

Step 1 - 10:

The number below refers to the step number on the diagnostic table.
2. This test checks to see if the relay is causing the high voltage problem.
5. This test checks to see if the PIM is causing the problem.