DTC P1597-A: SPEED CONTROL SWITCH ALWAYS LOW Chrysler LHS II

Note. For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.

1. Using scan tool, read speed control ON/OFF switch voltage. If voltage is less than one volt, go to next step. If voltage is one volt or more, condition to set trouble code is not present at this time. SPEED CONTROL SWITCH ALWAYS LOW DTC sets when switch voltage is less than 4.5 volts for 2 minutes. Possible causes are: speed control switch shorted, PCM failure, speed control switch signal circuit shorted or shorted speed control switch. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) .
2. Using scan tool, still observing speed control switch ON/OFF voltage, disconnect speed control ON/OFF switch 2-pin connector. If voltage changed to 5 volts, replace speed control ON/OFF switch. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) . If voltage did not change to 5 volts, go to next step.
3. Using scan tool, still observing speed control ON/OFF switch voltage, disconnect speed control RESUME/ACCEL switch connector. If voltage changed to 5 volts, replace speed control ON/OFF switch. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) . If voltage did not change to 5 volts, go to next step.
4. Using a DVOM, check resistance of speed control signal circuit at speed control ON/OFF switch connector. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground on speed control signal circuit. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) .
5. Disconnect Powertrain Control Module (PCM) connector. Using a DVOM, check resistance of speed control switch signal circuit between speed control ON/OFF switch 2-pin connector and ground. See «SPEED CONTROL SWITCH 2-PIN CONNECTOR WIRE IDENTIFICATION»(ref-576-S24091301192000030800000) table. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace PCM. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) .
6. Disconnect clock spring 5-pin connector. Using a DVOM, check resistance of speed control switch signal circuit between clock spring connector and PCM connector terminal No. 41. See «CLOCK SPRING 5-PIN CONNECTOR WIRE IDENTIFICATION»(ref-576-S42139930782000030800000) table and «PCM CONNECTOR WIRE IDENTIFICATION»(ref-576-S07517588942000030800000) table. If resistance is less than 5 ohms, repair short to ground on speed control switch signal circuit. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) . If resistance is 5 ohms or more, replace clock spring. Perform «TEST VER-4A: SPEED CONTROL VERIFICATION»(ref-576-S16464623272000030800000) .

SPEED CONTROL SWITCH 2-PIN CONNECTOR WIRE IDENTIFICATION

CLOCK SPRING 5-PIN CONNECTOR WIRE IDENTIFICATION

PCM CONNECTOR WIRE IDENTIFICATION