Circuit Test A-3: Pcm Power & Ground Circuit Check/Engine No Start
- Observe main relay (located in engine compartment relay/fuse box) while ignition is cycled on, then off. If sound is heard at relay, turn ignition off. Disconnect PCM harness connectors and go to step 5). If no sound is heard, go to next step.
- Turn ignition off. Remove main relay. Using an ohmmeter, ensure continuity exists between relay terminals No. 3 and 4. See Fig 1
. Continuity should not exist between relay terminals No. 1 and 2 . Apply battery voltage to terminal No. 3 and ground to terminal No. 4. Ensure continuity exists between terminals No. 1 and 2. Replace relay if continuity is not as specified. If relay is okay, go to next step.
Courtesy of SUZUKI OF AMERICA CORP.
- Ensure IG fuse (60-amp) in engine compartment relay/fuse box is okay. If fuse is blown, check for short circuit and repair as necessary. If fuse is okay, go to next step.
- Turn ignition off. Disconnect PCM harness connectors. Reinstall main relay. Turn ignition on. Using a voltmeter, measure voltage between ground and PCM harness connector "A", terminal No. 22 (Green wire). If reading is 10-14 volts, go to next step. If reading is not as specified, repair open Black/White wire between IG fuse (60-amp) and main relay, or open Green wire between main relay and PCM. Retest system.
- Using a fused jumper wire, connect PCM harness connector "A", terminal No. 22 (Green wire) to ground. Turn ignition on. Using a voltmeter, measure voltage between ground and PCM harness connector "A", terminal No. 2 (Red/Black wire). If reading is 10-14 volts, go to next step. If reading is not as specified, repair open Red wire between FI fuse (15-amp) and main relay, or open Red/Black wire between PCM and main relay. Retest system.
- Check for open Black or Black/Orange wire (PCM ground wires). Repair as necessary. If wires are okay, replace PCM. Retest system.