Powertrain Control Module (PCM)

P1501-VEHICLE SPEED SENSOR 1/2 CORRELATION - DRIVE WHEELS (Equipped with ABS)

For a complete wiring diagram, refer to the Wiring Information. Electrical Diagrams

- When Monitored:
Ignition on and the vehicle moving. Speed control is learned and the speed control is trying to be activated.

- Set Condition:
The Powertrain Control Module (PCM) recognizes the rear wheel speed is greater than the front wheel speed.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC

NOTE: The following items must be performed before continuing.
- Pinion Factor and Tire Size MUST be programmed in the ABS Module.
- All Bus Communication DTCs MUST be diagnosed.
- All related Vehicle Speed and Wheel Speed DTCs that may be active in the ABS Module MUST be diagnosed. Testing and Inspection for the correct procedure.

1. Ignition on, engine not running.
2. With a scan tool, read the DTCs.

Is the DTC active at this time?

Yes

- Go To 2

No

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Checking for an Intermittent DTC.

2. VISUAL INSPECTION

NOTE: This code can set due to the following conditions:
- Unequal tire circumference between the tires on the vehicle.
- Front or rear wheels moving while the opposite wheels are not. (i.e., wheels slipping on loose gravel, ice or hard acceleration).

1. Check tire pressure of all the tires.
2. Check tire wear on all the tires.
3. Ask the customer what the road and driving conditions were like when the fault set.

Were any of the above conditions found?

Yes

- Repair as necessary. If the code set during a front or rear wheel spin condition, no repair is necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 3

3. POWERTRAIN CONTROL MODULE (PCM)

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace and program the Powertrain Control Module.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.