B2136

Step 1: Perform visual inspection of the instrument cluster wiring harness and BCM connectors for signs of damage, chafing, melting, or pinched wires. Check for aftermarket installations that may tie into the warning lamp circuit.

Step 2: Disconnect the instrument cluster connector and use a digital multimeter to measure voltage on the park brake warning lamp wire at the cluster harness connector with ignition on. Should read 0V; constant battery voltage confirms short to power in the harness between BCM and cluster.

Step 3: If voltage is present at disconnected cluster, disconnect BCM connector and check for voltage at the same circuit. If voltage disappears, BCM has internal short. If voltage remains, short exists in the wiring harness between the two components.

Step 4: Inspect wiring harness routing near sharp edges, mounting brackets, and areas where harness passes through firewalls or body panels. Use wiring diagram to trace circuit and locate short point.

Step 5: If no voltage found at disconnected cluster in Step 2, reconnect cluster and monitor circuit with multimeter while wiggling harness and connectors to locate intermittent short. Test instrument cluster on known-good vehicle if available, or replace cluster if internal short suspected.

Step 6: After repair, clear codes, cycle ignition and parking brake multiple times, and verify warning lamp operates correctly with parking brake application and release. Confirm no codes return.