Test Description
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step tests for a faulty tow/haul switch.
- 3: This step tests for voltage input from the BCM to the tow/haul switch.
- 6: This step tests for ground integrity.
DTC P071A
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 |
|
- | Go to Control Module References | Go to Step 2 |
| 2 |
|
- | Go to Step 7 | Go to Step 3 |
| 3 | Using the DMM and the J 35616
, measure the voltage at the tow/haul switch signal circuit of the tow/haul switch connector. Is ignition voltage measured? |
- | Go to Step 6 | Go to Step 4 |
| 4 | Using the DMM and the J 35616
, measure the voltage at the tow/haul switch signal circuit of the body control module (BCM). Is ignition voltage measured? |
- | Go to Step 5 | Go to Step 8 |
| 5 | Test the signal circuit of the tow/haul switch for an open or shorted condition. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? |
- | Go to Step 9 | Go to Testing for Intermittent Conditions and Poor Connections |
| 6 | Test the ground circuit of the tow/haul switch for an open or shorted condition. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? |
- | Go to Step 9 | Go to Testing for Intermittent Conditions and Poor Connections |
| 7 | Replace the tow/haul switch. Refer to Shift Lever Replacement . Did you complete the replacement? |
- | Go to Step 9 | - |
| 8 | Replace the BCM. Refer to Control Module References . Did you find and correct the condition? |
- | Go to Step 9 | - |
| 9 | After the repair is complete, observe Tow/Haul Mode on the scan tool display, while cycling the tow/haul switch. Does the scan tool display Active when the switch is first pressed, and then Inactive when the switch is pressed again? |
- | System OK | Go to Step 1 |