Circuit Description
The body control module (BCM) monitors the ignition 1 voltage circuit 339,
the ignition 2 voltage circuit 743 and the engine run flag (ERF). The
ERF is a serial data message from the engine controller.
Conditions for Setting the DTC
| • | Ignition in the RUN position |
| • | Ignition 1 circuit 339 shorted-to-ground or open |
| • | Engine run flag present (engine running) |
| • | All conditions for greater than 1.2 seconds |
| • | No telltale illumination |
Diagnostic Aids
| • | Check for a poor connection at the BCM. Inspect the harness connectors
for backed-out terminals, improper terminal mating, broken connector locks, improperly
formed or damaged terminals and poor terminal-to-wire connection (terminal crimped
over wire insulation and not the conductors). |
| • | Inspect the wiring harness for damage. Check for broken or chaffed insulation. |
| • | If the fault is suspected to be intermittent, wiggling the harness wiring
may help in locating the fault. |
