The Throttle Actuator Control (TAC) System uses an ignition voltage supply separate from the powertrain control module (PCM) supply. If the PCM detects a voltage difference between the 2 circuits, DTC P1682 will set.
This diagnostic procedure supports the following DTC:
DTC P1682 Ignition 1 Switch Circuit 2
• | The ignition is ON. |
• | DTC P1682 runs continuously when the ignition is ON. |
The ignition 1 voltage is less than 10 volts for more than 2 seconds.
• | The control module stores the DTC information into memory when the diagnostic runs and fails. |
• | The malfunction indicator lamp (MIL) will not illuminate. |
• | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
• | The driver information center, if equipped, may display a message. |
• | A current DTC Last Test Failed clears when the diagnostic runs and passes. |
• | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
• | Clear the DTC with a scan tool. |
Step | Action | Values | Yes | No |
---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the DTC fail this ignition? | -- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
3 | With a test lamp connected to ground, probe both sides of the electronic throttle control (ETC) fuse. Does the test lamp illuminate on both sides of the fuse? | -- | Go to Step 5 | Go to Step 4 |
4 | Does the test lamp illuminate on one side of the fuse? | -- | Go to Step 6 | |
5 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 |
6 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 |
7 | Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 8 |
8 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 10 |
10 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK |