NTC-3: Speed Control On/Off Switch

Possible Causes

• Signal circuit open or shorted.
• S/C ON/OFF switch defective.
• S/C RESUME/ACCEL switch defective.
• Defective PCM.
• Defective clockspring.

1. Turn ignition on. Using scan tool, read S/C switch voltage. If voltage is more than 4 volts, go to next step. If voltage is 4 volts or less, go to step  4.
2. Turn ignition off. Disconnect S/C ON/OFF switch. Inspect connector. Clean or repair connections as necessary. Connect a jumper wire between ground and S/C switch signal circuit at S/C ON/OFF switch connector (Dark Green/Red wire on all models except Ram Van and Ram Wagon; wire color is not available for Ram Van and Ram Wagon). Start engine. Turn speed control on. Using scan tool, read S/C switch voltage. If voltage is one volt or more, go to next step. If voltage is less than one volt, replace S/C ON/OFF switch. Perform TEST VER-4A  under VERIFICATION TESTS.
3. Using a voltmeter, measure voltage on S/C switch signal circuit (Dark Green/Red wire on all models except Ram Van and Ram Wagon; wire color is not available for Ram Van and Ram Wagon). If voltage is less than 4 volts, repair high resistance in S/C switch signal circuit. If voltage is more than 6 volts, repair short to voltage. If voltage is 4-6 volts, replace PCM. After repair, perform TEST VER-4A  under VERIFICATION TESTS.
4. Turn ignition off. Disconnect clockspring connector at steering column. Start engine. Turn speed control on. Using scan tool, read S/C switch voltage. If voltage is 4 volts or less, go to next step. If voltage is more than 4 volts, replace clockspring. Perform TEST VER-4A  under VERIFICATION TESTS.
5. Turn ignition off. Disconnect RESUME/ACCEL switch. Start engine. Turn speed control on. Using scan tool, read S/C switch voltage. If voltage is 4 volts or less, go to next step. If voltage is more than 4 volts, replace RESUME/ACCEL switch. Perform TEST VER-4A  under VERIFICATION TESTS.
6. Turn ignition off. Disconnect S/C ON/OFF switch. Start engine. Using scan tool, turn speed control on. Using scan tool, read S/C switch voltage. If voltage is 4 volts or less, go to next step. If voltage is more than 4 volts, replace ON/OFF switch. Perform TEST VER-4A  under VERIFICATION TESTS.
7. Turn ignition off. Disconnect PCM. Inspect connectors. Clean or repair connections as necessary. Using an ohmmeter, measure resistance between ground and S/C switch signal circuit at PCM connector C3, terminal No. 32 (White/Light Green wire on Ram Van and Ram Wagon; Red/Light Green wire on all other models). If resistance is less than 5 ohms, repair short to ground. If resistance is 5 ohms or more, replace PCM. After repair, perform TEST VER-4A  under VERIFICATION TESTS.