Circuit Description
The powertrain control module (PCM) has the ability to inhibit cruise control if conditions are detected which would make cruise control operation undesirable.
The PCM will interrupt the ground on the cruise inhibit circuit to request that cruise control be disengaged.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1554 Cruise Control Feedback Circuit
Conditions for Running the DTC
The ignition is ON.
The PCM is commanding the cruise control module to inhibit cruise control operation.
Conditions for Setting the DTC
The PCM detects a cruise engaged signal from the cruise control module, while inhibiting cruise control operation.
Action Taken When the DTC Sets
The PCM stores the conditions present when the DTC set as Failure Records data only.
Conditions for Clearing the DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | The PCM receives a clear code command from the scan tool. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Cruise Control Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the Cruise Active parameter display Engaged? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 |
Does the Cruise Active parameter display Engaged? | Go to Step 4 | Go to Step 5 |
4 | Test the cruise control engaged signal circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 6 |
5 | Inspect for poor connections at the harness connector of the cruise control module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
7 | Replace the cruise control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 9 | -- |
8 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
