P0585-S/C SWITCH PLAUSIBILITY BETWEEN SWITCH #1 AND #2
For a complete wiring diagram Refer to Section 8W
- When Monitored:
With the ignition on.
- Set Condition:
The ECM detects a discrepency between S/C Switch #1 and S/C Switch #2 signals for 10.0 seconds.
| Possible Causes |
| INTERMITTENT CONDITION |
| HIGH RESISTANCE IN THE S/C SWITCH SIGNAL CIRCUIT |
| HIGH RESISTANCE IN THE S/C SWITCH GROUND CIRCUIT |
| S/C SWITCHES |
| ENGINE CONTROL MODULE |
Diagnostic Test
1. CHECK FOR ACTIVE DTCNOTE: If the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.
Turn the ignition on.
With the scan tool, erase ECM DTCs.
Test drive the vehicle and activate the Speed Control.
At some point during the test drive, press each of the S/C Switch buttons.
With the scan tool, read ECM DTCs.
Did this DTC set again?
Yes
- Go To2
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
2. HIGH RESISTANCE IN THE S/C SWITCH SIGNAL CIRCUIT
Turn the ignition off.
Disconnect the S/C Switch harness connectors.
Disconnect the ECM harness connectors.
Measure the resistance of the S/C Switch #1 Signal circuit and the S/C Switch #2 Signal circuit between each S/C Switch harness connector and the ECM harness connector.
Is the resistance below 10.0 ohms for each measurement?
Yes
- Go To3
No
- Repair the S/C Switch Signal circuit(s) for high resistance.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
3. HIGH RESISTANCE IN THE SENSOR GROUND CIRCUIT
Measure the resistance of the Sensor Ground circuit between each S/C Switch harness connector and the ECM harness connector.
Is the resistance below 10.0 ohms for both measurements?
Yes
- Go To4
No
- Repair the S/C Switch Ground circuit for high resistance.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
4. S/C SWITCHES
Turn the ignition off.
Replace the S/C Switches.
Connect ECM harness connectors.
Turn the ignition on.
With the scan tool, erase ECM DTCs.
Test drive the vehicle and activate the Speed Control.
At some point during the test drive, press each of the S/C Switch buttons.
Monitor the scan tool for ECM DTCs.
Did this DTC set again?
Yes
- Replace and program the Engine Control Module in accordance with the Service Information.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- The repair is complete.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).