Diagnostic Procedure
WARNING: This page is about a different car, the 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
- If FREEZE FRAME DATA has been recorded, go to next step. If FREEZE FRAME DATA has not been recorded, record FREEZE FRAME DATA. Go to next step.
- Verify Related Repair Information Availability - Check for related Service Bulletins and/or on-line repair information availability. If any related repair information is available, perform repair or diagnosis according to available repair information. If vehicle is not repaired, go to next step. If related repair information is not available, go to next step.
- Verify Current Input Signal Status - Is Concern Intermittent Or Constant -
Connect WDS or equivalent to DLC-2. Start engine. Access VSS PID using WDS or equivalent.
- Vehicle speed 12.4 MPH
- Vehicle speed 24.8 MPH
- Verify Vehicle Type - Verify vehicle type. If vehicle is equipped with a MTX without ABS/TCS, go to next step. If vehicle is equipped with a ATX without ABS/TCS, go to applicable DTC inspection. Refer to DIAGNOSTIC TROUBLE CODE DEFINITIONS . If vehicle is equipped with ABS/TCS, go to applicable DTC inspection.
- Inspect VSS Connector For Poor Connection - Verify VSS connector is connected securely. If connection is okay, go to next step. If connector is loose, reconnect VSS harness connector securely. After repair, go to step 11.
- Inspect VSS Circuit For Short To Ground -
Turn ignition off. Check continuity between following circuits:
- VSS harness connector terminal "A" (Yellow/Red wire) and body ground. See Fig 1
- VSS harness connector terminal "B" (Gray/Red wire) and body ground
- Inspect VSS Circuit For Short To Power -
Turn ignition off. Disconnect VSS harness connector. Turn ignition on, engine off. Measure voltage at following terminals:
- VSS harness connector terminal "A" (Yellow/Red wire) and body ground
- VSS harness connector terminal "B" (Gray/Red wire) and body ground
- Inspect VSS - Perform VSS inspection. Refer to VEHICLE SPEED SENSOR under ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. If VSS is okay, go to next step. If VSS is faulty, replace VSS. After repair, go to step 11.
- Inspect PCM Connector For Poor Connection - Disconnect PCM 104-pin harness connector. See Fig 1. Inspect for poor connection (such as damaged, pulled-out terminals or corrosion). If malfunction is not present, go to next step. If any malfunction is present, repair suspected terminal or replace wire harness. After repair, go to step 11.
- Inspect VSS Circuit For Open Circuit -
Turn ignition off. Check for continuity between following harnesses:
- VSS harness connector terminal "A" and PCM 104-pin harness connector terminal No. 57
- VSS harness connector terminal "B" and PCM 104-pin harness connector terminal No. 84
- Verify Trouble Shooting Of DTC P0500 Is Completed -
Make sure to reconnect all disconnected connectors. Turn ignition on, engine off. Clear DTC from PCM memory using WDS or equivalent. See CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. Warm up engine. Access RPM and LOAD PID using WDS or equivalent. Drive vehicle under following conditions for 18 seconds.
- Engine speed: 2000 RPM or more
- Gear Position: Gear is in position other than Neutral
- Load: 40 percent or more
- Verify After Repair Procedure - Using scan tool, perform After Repair Procedure. See AFTER REPAIR PROCEDURE . If any DTCs are present, go to appropriate DTC inspection. Refer to DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are present, trouble shooting is complete.