P0590-SPEED CONTROL SWITCH 2 STUCK
For a complete wiring diagram Refer to Section 8W
- When Monitored:
With the ignition on and no other S/C Switch DTCs present.
- Set Condition:
The S/C Switch 2 Signal indicates that a switch is pressed for more than 60 seconds.
| Possible Causes |
| INTERMITTENT DTC |
| (V72) S/C SWITCH 2 SIGNAL CIRCUIT SHORTED TO VOLTAGE |
| (V937) S/C SWITCH GROUND CIRCUIT SHORTED TO VOLTAGE |
| (V72) S/C SWITCH 2 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE |
| (V937) S/C SWITCH GROUND CIRCUIT OPEN OR HIGH RESISTANCE |
| (V72) S/C SWITCH 2 SIGNAL CIRCUIT SHORTED TO GROUND |
| SPEED CONTROL SWITCH |
| ENGINE CONTROL MODULE (ECM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
Diagnostic Test
1. S/C SWITCH VOLTAGES OUT OF RANGE| KEY | SIGNAL 1 | SIGNAL 2 | ||
| LO LIMIT | HI LIMIT | LO LIMIT | HI LIMIT | |
| RELEASED | 4.36 | 4.69 | 4.36 | 4.69 |
| ON-OFF | 0.50 | 1.10 | 3.53 | 3.90 |
| SET | 3.16 | 3.53 | 1.56 | 1.18 |
| RESUME-ACCEL | 3.84 | 4.19 | 1.70 | 2.43 |
| CANCEL | 1.59 | 1.97 | 2.43 | 3.22 |
Turn the ignition on.
With the scan tool, monitor the S/C Switch signal voltages.
Press each button while noting the voltage readings for each circuit.
Are the S/C Switch voltages within the ranges specified in the table when each button is pressed?
Yes
Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go To2
2. (V72) S/C SWITCH 2 SIGNAL CIRCUIT VOLTAGE
Turn the ignition off.
Disconnect the Speed Control Switch harness connector.
Turn the ignition on.
Measure the voltage of the (V72) S/C Switch 2 Signal Circuit at the Speed Control Switch.
Select the appropriate voltage reading.
4.5 to 5.5 volts
- Go To3
Below 4.5 volts
- Go To6
Above 5.5 volts
- Go To8
3. (V937) S/C SWITCH GROUND CIRCUIT OPEN CIRCUIT OR HIGH RESISTANCE
Turn the ignition off.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance of the (V937) S/C Switch Ground circuit between the Speed Control Switch harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?
Yes
- Go To4
No
- Repair the (V937) S/C Switch Ground circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
4. (V937) S/C SWITCH GROUND CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Remove the Main Relay.
Connect a jumper wire between cavity B7 and cavity B9 of the Main Relay connector.
Turn the ignition on.
Measure the voltage of the (V937) S/C Switch Ground circuit.
Is there any voltage present?
Yes
- Repair the (V937) S/C Switch Ground circuit for a short to voltage.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go to 5
5. S/C SWITCH
Turn the ignition off.
Connect the Engine Control Module (ECM) harness connector.
Turn the ignition on.
With the scan tool, monitor the S/C Switch Voltage.
While monitoring the scan tool, connect a jumper wire between the (V72) S/C Switch 2 Signal circuit and the (V937) S/C Switch Ground circuit in the S/C Switch harness connector.
Does the scan tool display below 0.1 volt with the jumper wire in place?
Yes
- Replace the Speed Control Switch in accordance with the Service Information.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go to 9
6. (V72) S/C SWITCH 2 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE
Turn the ignition off.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance of the (V72) S/C Switch 2 Signal circuit between the Speed Control Switch harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?
Yes
- Go To7
No
- Repair the (V71) S/C Switch 2 Signal circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
7. (V72) S/C SWITCH 2 SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (V72) S/C Switch 2 Signal circuit.
Is the resistance above 1000 ohms?
Yes
- Go to 9
No
- Repair the (V72) S/C Switch 2 Signal circuit for a short to ground.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
8. (V72) S/C SWITCH 2 SIGNAL CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Disconnect the Engine Control Module (ECM) harness connector.
Remove the Main Relay.
Connect a jumper wire between cavity B7 and cavity B9 of the Main Relay connector.
Turn the ignition on.
Measure the voltage of the (V72) S/C Switch 2 Signal circuit.
Is there any voltage present?
Yes
- Repair the (V72) S/C Switch 2 Signal circuit for a short to voltage.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go to 9
9. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Speed Control Switch and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Refer to any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Replace the Engine Control Module (ECM) in accordance with the Service Information.
- Perform the ECM Verification Test Ver.1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)