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 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 FI fuse (15-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 "C", terminal No. 20, then PCM harness connector "A", terminal No. 22. If reading is 10-14 volts at each terminal, go to next step. If reading is not as specified, repair open in Black/White wire between PCM and MIL bulb, White Red wire between FI fuse and main relay, or Blue/Black wire between PCM and main relay. Retest system.
- Using a fused jumper wire, connect PCM harness connector "A", terminal No. 22 (Blue/Black wire) to ground. Turn ignition on. Using a voltmeter, measure voltage between ground and PCM harness connector "A", terminal No. 2 (White/Blue wire). If reading is 10-14 volts, go to next step. If reading is not as specified, repair open White/Red wire between FI fuse and main relay, or open White/Blue wire between PCM and main relay. Retest system.
- Check for open Black/Green, Black/Blue, or Black/Red wires (PCM ground wires). Repair as necessary. If wires are okay, replace PCM. Retest system.