Test Description
WARNING: This page is about a different car, the 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 Chevrolet TrailBlazer, and 2004 Buick Rainier. 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.
- 7: If the TP indicated angle does not follow the movement of the throttle blade and no TP sensor DTCs are set, there is a mechanical condition with the throttle shaft or the TP sensor.
- 18: Locating and repairing an individual condition may correct more than 1 DTC.
DTC P1516
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views |
|||
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | Go to Diagnostic System Check - Engine Controls |
| 2 | Is DTC U0107 set? | Go to DTC P2135 | Go to Step 3 |
| 3 | Is DTC P2135 set? | Go to DTC P2135 | Go to Step 4 |
| 4 |
|
Go to Diagnostic Aids | Go to Step 5 |
| 5 |
|
Go to Step 17 | Go to Step 6 |
| 6 | With your hand, slowly open the throttle plate to WOT and back to the closed position several times. Does the throttle plate move smoothly without binding in both directions? |
Go to Step 7 | Go to Step 14 |
| 7 |
|
Go to Step 8 | Go to Step 15 |
| 8 |
|
Go to Step 17 | Go to Step 9 |
| 9 | Test each TAC motor circuit for an open or high resistance with a DMM. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 17 | Go to Step 10 |
| 10 | Test each TAC motor circuit for a short to ground with a DMM. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 17 | Go to Step 11 |
| 11 |
|
Go to Step 17 | Go to Step 12 |
| 12 |
|
Go to Step 13 | Go to Step 15 |
| 13 | Inspect for poor connections at the TAC motor harness connector. Refer to Testing for Intermittent Conditions and Poor Connections
and Repairing Connector Terminals
in Wiring Systems. Did you find and correct the condition? |
Go to Step 17 | Go to Step 14 |
| 14 | Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement
. Did you complete the replacement? |
Go to Step 15 | - |
| 15 | Inspect for poor connections at the TAC module harness connectors. Refer to Testing for Intermittent Conditions and Poor Connections
and Repairing Connector Terminals
in Wiring Systems. Did you find and correct the condition? |
Go to Step 17 | Go to Step 16 |
| 16 | Replace the TAC module. Refer to Throttle Actuator Control (TAC) Module Replacement
. Did you complete the replacement? |
Go to Step 17 | - |
| 17 |
|
Go to Step 2 | Go to Step 18 |
| 18 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? |
Go to Diagnostic Trouble Code (DTC) List | System OK |