PCM is located in right rear corner of engine compartment. Check PCM connectors for corroded or loose connections. Repair as necessary. Disconnect PCM connectors. Using DVOM, check for battery voltage between chassis ground and battery power circuits at PCM harness connector C1 terminal No. 2 (2.0L) or No. 35 (2.5L). See Fig 1 or Fig 5 . If battery voltage is present, go to next step. If battery voltage is not present, check for blown DOME fuse. If DOME fuse is okay, check for open circuit between DOME fuse and PCM.
Turn ignition on. Using DVOM, check for battery voltage between chassis ground and ignition power circuits at PCM harness connector C2 terminal No. 20 (2.0L), or PCM harness connector C4 terminal No. 3 (2.5L). See Fig 2 or Fig 8 . If battery voltage is present, fused power circuits are okay. If battery voltage is not present, check IG fuse. If fuse is okay, check for open circuit between battery, ignition switch, and PCM ignition power terminals. If circuits are okay, check for faulty ignition switch.

Fig 1: Identifying PCM Harness Connector C1 Terminals (2.0L)

Courtesy of GENERAL MOTORS CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Power Circuits