Diagnosis & Repair Procedure
NOTE:
For better performance and results of this diagnostic procedure, usage of appropriate wiring diagram is recommended. See ENGINE PERFORMANCE
in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
NOTE:
Perform all voltage and resistance tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use an ohmmeter to isolate wiring harness shorts or opens.
- If engine system check has been performed, go to next step. If engine system check has not been performed, perform TEST D: ENGINE SYSTEM CHECK under SYSTEM TESTS, then go to next step.
- Drive vehicle and check speedometer for vehicle speed indication. If speedometer indicates vehicle speed, go to next step. If speedometer does not indicates vehicle speed, go to step 5.
- Drive vehicle. Using SUZUKI scan tool or equivalent, check if vehicle speed is displayed. If vehicle speed is not displayed on scan tool, go to next step. If vehicle speed is displayed on scan tool, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO-CODES article. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Remove combination meter. See COMBINATION METER under REMOVAL & INSTALLATION in INSTRUMENT PANELS - AERIO article. Disconnect combination meter 22-pin harness connector G21. Turn ignition switch to ON position. Measure voltage between ground and combination meter harness connector G21 terminal No. 7 (Purple wire). See Fig 1. If voltage is 4-5 volts, replace faulty speedometer. After repair, repeat DTC CONFIRMATION TEST . If voltage is not 4-5 volts, check for open or short circuit in Purple wire between ECM, VSS and combination meter. If open or short circuit is found, repair as necessary and repeat DTC CONFIRMATION TEST . If open or short circuit is not found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Disconnect VSS 3-pin harness connector C20. See Figure. Check VSS harness connector terminals for corrosion or poor connection. If connector terminals are faulty, repair as necessary and repeat DTC CONFIRMATION TEST . If connector terminals are okay, turn ignition switch to ON position and measure voltage between ground and VSS harness connector C20 terminal No. 3 (Black/Red wire). See Fig 2. If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair open or short circuit in Black/Red wire between VSS and main relay. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Check for continuity between ground and VSS harness connector C20 terminal No. 2 (Black/Orange wire). See Fig 2. If continuity is found, go to next step. If continuity is not found, repair open circuit in Black/Orange wire between VSS and ground. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to ON position. Measure voltage between ground and VSS harness connector C20 terminal No. 1 (Purple wire). If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to step 9.
- Turn ignition switch to LOCK position. Remove combination meter. See COMBINATION METER under REMOVAL & INSTALLATION in INSTRUMENT PANELS - AERIO article. Disconnect combination meter 22-pin harness connector G21. Turn ignition switch to ON position. Measure voltage between ground and combination meter harness connector G21 terminal No. 7 (Purple wire). See Fig 1. If voltage is not 4-5 volts, go to next step. If voltage is 4-5 volts, replace faulty speedometer. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to ON position. Measure voltage between ground and VSS harness connector C20 terminal No. 1 (Purple wire). If voltage is not 4-5 volts, go to next step. If voltage is 4-5 volts, go to step 13.
- Turn ignition switch to LOCK position. Locate ECM harness connector G04. See Figure. Turn ignition switch to ON position. Backprobe and measure voltage between ground and ECM harness connector G04 terminal No. 27 (Purple wire). See Figure. If voltage is not 4-5 volts, go to next step. If voltage is 4-5 volts, repair open circuit in Purple wire between ECM and VSS. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Disconnect ECM harness connector G04. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector G04 terminal No. 27 (Purple wire). See Figure. If voltage is zero volt, go to next step. If any voltage is found, repair short to voltage in Purple wire between ECM and VSS. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Measure resistance between ground and ECM harness connector G04 terminal No. 27 (Purple wire). See Figure. If resistance is infinity, go to next step. If any resistance is found, check short to ground in Purple wire between ECM and VSS. If short to ground is found, repair as necessary and repeat DTC CONFIRMATION TEST . If no short to ground is found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .
- Remove VSS. See VEHICLE SPEED SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION article. Perform component visual inspection (signal rotor for damage). If VSS is okay, go to next step. If VSS is faulty, replace VSS and repeat DTC CONFIRMATION TEST .
- Perform VSS component test. See VEHICLE SPEED SENSOR under ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. If VSS is faulty, replace VSS and repeat DTC CONFIRMATION TEST . If VSS is okay, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .