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Wiper Switch MUX CKT Open

  1. Turn ignition on. Using scan tool, erase BCM DTCs. Turn ignition off, then on. Turn wiper switch to each intermittent position, then low and high speed positions. Read BCM DTCs. If scan tool displays WIPER SWITCH MUX CKT OPEN, go to next step. If scan tool does not display WIPER SWITCH MUX CKT OPEN, test is complete.
  2. Turn ignition off. Disconnect right multi-function switch connector. Disconnect Body Control Module (BCM) C2 connector. Using ohmmeter, measure resistance of Dark Blue/Yellow wire between terminal No. 22 on BCM C2 harness connector and terminal No. 7 on right multi-function switch harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open Dark Blue/Yellow wire.
  3. Using ohmmeter, measure resistance of Dark Green/Red wire between terminal No. 11 on BCM C2 harness connector and terminal No. 8 on right multi-function switch harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open Dark Green/Red wire.
  4. Ensure wiper switch is in OFF position. Using ohmmeter, measure resistance between terminals No. 7 and 8 on right multi-function switch component connector. Rotate wiper switch to HIGH position while monitoring ohmmeter. If resistance is less than 40 ohms in any position, replace right multi-function switch. If resistance is not less than 40 ohms in any position, go to next step.
  5. Ensure all components are connected. Using jumper wire, backprobe BCM C2 connector. Connect jumper wire between terminals No. 11 and 22 on BCM C2 connector. Turn ignition on. Using scan tool, read WIPER MODE SW VOLTS sensor. If sensor volts are greater than 4.8 volts, replace BCM. If sensor volts are 4.8 volts or less, test is complete.
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