Washer System
The diagnosis found here addresses an electrically inoperative washer system. However, these tests may not prove conclusive in the diagnosis of the Central Timer Module (CTM). In order to obtain conclusive testing of the CTM, the Programmable Communications Interface (PCI) data bus network and all of the electronic modules that provide inputs to or receive outputs from the washer system components must be checked. The most reliable, efficient, and accurate means to diagnose the CTM requires the use of a DRBIII(R) scan tool. Refer to the appropriate diagnostic information. If the washer pump/motor operates, but no washer fluid is emitted from the washer nozzles, be certain to check the fluid level in the reservoir. Also inspect the washer system components as required. (Refer to INSPECTION-WIPER & WASHER SYSTEM ). Refer toSYSTEM WIRING DIAGRAMS .
- Turn the ignition switch to the On position. Turn the multi-function switch wiper control knob to the Lo or Hi speed position. Check whether the wipers operate. If OK, go to Step 2. If not OK, repair the wiper system as required before proceeding with the following tests. Refer to WIPER SYSTEM .
- Turn the multi-function switch wiper control knob to the Off position. Depress the control knob to the Wash position. The washer pump should operate and the wipers should operate for as long as the control knob is depressed. The wipers should continue to operate for about three sweep cycles after the control knob is released before they park. If the wipers are OK, but the washers are not, go to Step 3. If the washers are OK, but the wipers are not, go to Step 5.
- Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Disconnect the headlamp and dash wire harness connector for the washer pump/motor from the motor connector receptacle. Measure the resistance between the ground circuit cavity of the headlamp and dash wire harness connector for the washer pump/motor and a good ground. The meter should read zero ohms. If OK, go to Step 4. If not OK, repair the open ground circuit to ground (G112) as required.
- Reconnect the battery negative cable. Turn the ignition switch to the On position. With the control knob of the multi-function switch depressed to the Wash position, check for battery voltage at the front washer pump/motor control circuit cavity of the headlamp and dash wire harness connector for the washer pump/motor. If OK, replace the faulty washer pump/motor. If not OK, repair the open front washer pump/motor control circuit between the washer pump/motor and the CTM as required.
- Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Disconnect the instrument panel wire harness connector (Connector C1) for the CTM from the CTM connector receptacle. Reconnect the battery negative cable. Turn the ignition switch to the On position. With the control knob of the multi-function switch depressed to the Wash position, check for battery voltage at the front washer pump/motor control circuit cavity of the instrument panel wire harness connector (Connector C1) for the CTM. If OK, proceed to the diagnosis for the wiper relay. (Refer to DIAGNOSIS AND TESTING-WIPER RELAY ). If not OK, repair the open front washer pump/motor control circuit between the CTM and the multi-function switch as required.