Front Wiper & Washer System Test
FRONT WIPER SYSTEMThe diagnosis found here addresses an electrically inoperative front wiper system. If the front wiper motor operates, but the wipers do not move on the windshield, replace the faulty front wiper module. If the front wipers operate, but chatter, lift, or do not clear the glass, clean and inspect the front wiper system components as required. (Refer to FRONT WIPERS/WASHERS - INSPECTION) and (Refer to ELECTRICAL/FRONT WIPERS/ WASHERS - CLEANING). Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.
The following tests will help to diagnose the hard wired components and circuits of the front wiper 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 wiper system components must be checked. The most reliable, efficient, and accurate means to diagnose the CTM requires the use of a DRB III scan tool. Refer to the appropriate diagnostic information. The DRB III scan tool can provide confirmation that the PCI data bus is functional, that all of the electronic modules are sending and receiving the proper messages on the PCI data bus, and that the front wiper relay is being sent the proper hard wired outputs by the CTM for it to perform its front wiper system functions.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, SEAT BELT TENSIONER, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
1. Check the fused ignition switch output (RUN/ACC) fuse (Fuse 5 - 20 ampere) in the Junction Block (JB). If OK, go to Step 2. If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
2. Turn the ignition switch to the ON position. Check for battery voltage at the fused ignition switch output (RUN/ACC) fuse (Fuse 5 - 20 ampere) in the JB. If OK, go to Step 3. If not OK, repair the open fused ignition switch output (RUN/ACC) circuit between the JB and the ignition switch as required.
3. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the instrument panel wire harness connector for the multi-function switch from the switch connector receptacle. Reconnect the battery negative cable. Turn the ignition switch to the ON position. Check for battery voltage at the fused ignition switch output (RUN/ACC) circuit cavity of the instrument panel wire harness connector for the multi-function switch. If OK, go to Step 4. If not OK, repair the open fused ignition switch output (RUN/ACC) circuit between the multi-function switch and the JB as required.
4. If the problem being diagnosed involves only the intermittent wipe feature, go to Step 5. If the problem being diagnosed involves all wiper modes, or only the Low and/or High speed modes, go to Step 7.
5. 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. Check for continuity between the intermittent front wiper mode sense circuit cavities of the instrument panel wire harness connector for the multi-function switch and the instrument panel wire harness connector (Connector C1) for the CTM. There should be continuity If OK, go to Step 6. If not OK, repair the open intermittent front wiper mode sense circuit between the multi-function switch and the CTM as required.
6. Check for continuity between the intermittent front wiper switch signal circuit cavities of the instrument panel wire harness connector for the multi-function switch and the instrument panel wire harness connector (Connector C1) for the CTM. There should be continuity. If OK, proceed to the diagnosis for the front wiper relay. (Refer to ELECTRICAL/FRONT WIPERS/WASHERS/FRONT WIPER RELAY - DIAGNOSIS AND TESTING). If not OK, repair the open intermittent front wiper switch signal circuit between the multi-function switch and the CTM as required.
7. Check for continuity between the two front wiper low speed circuit cavities of the instrument panel wire harness connector for the multi-function switch. There should be continuity. If OK, go to Step 8. If not OK, repair the open front wiper low speed circuit between the two cavities of the instrument panel wire harness connector for the multi-function switch as required.
8. Test the multi-function switch continuity. (Refer to ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/MULTI-FUNCTION SWITCH - DIAGNOSIS AND TESTING). If the multi-function switch tests OK, reconnect the instrument panel wire harness connector for the multi-function switch to the switch connector receptacle and go to Step 9. If not OK, replace the faulty multi-function switch and test the front wiper system operation again. If still not OK, go to Step 9.
9. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Measure the resistance between the headlamp and dash wire harness ground wire for the front wiper motor and a good ground. The meter should read zero ohms. If OK, go to Step 10. If not OK, repair the open ground circuit to ground (G11 3) as required.
10. Disconnect the headlamp and dash wire harness connector for the front wiper module from the front wiper motor pigtail wire connector. Reconnect the battery negative cable. Turn the ignition switch to the ON position. Place the multi-function switch in the positions indicated in the tests below, and check for battery voltage at the appropriate cavity of the headlamp and dash wire harness connector for the front wiper motor.
a. Check for battery voltage at the fused ignition switch output (RUN/ACC) circuit cavity of the headlamp and dash wire harness connector for the front wiper module with the multi-function switch in any position. If OK, go to Step b. If not OK, repair the open fused ignition switch output (RUN/ACC) circuit between the front wiper module and the JB as required.
b. Check for battery voltage at the front wiper low speed circuit cavity of the headlamp and dash wire harness connector for the front wiper module with the multi-function switch in the Lo position. If OK, go to Step c. If not OK, repair the open front wiper low speed circuit between the front wiper module and the multi-function switch as required.
c. Check for battery voltage at the front wiper high speed circuit cavity of the headlamp and dash wire harness connector for the front wiper module with the multi-function switch in the Hi position. If OK, go to Step d. If not OK, repair the open front wiper high speed circuit between the front wiper module and the multi-function switch as required.
d. Check for battery voltage at the front wiper park switch sense circuit cavity of the headlamp and dash wire harness connector for the front wiper module with the multi-function switch in the Lo or Hi position, then move the switch to the OFF position. The meter should switch between battery voltage and zero volts while the front wipers are cycling. The meter should read battery voltage when the switch is first moved to the OFF position until the front wipers park, and then read a steady zero volts. If not OK, replace the faulty front wiper module.
FRONT WASHER SYSTEM
The diagnosis found here addresses an electrically inoperative front 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 front washer system components must be checked. The most reliable, efficient, and accurate means to diagnose the CTM requires the use of a DRB III 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 ELECTRICAL/FRONT WIPERS/WASHERS - INSPECTION). Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, SEAT BELT TENSIONER, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
1. 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 front 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 FRONT WIPER SYSTEM.
2. Turn the multi-function switch wiper control knob to the OFF position. Depress the control knob to the Wash position. The front washer pump should operate and the front wipers should operate for as long as the control knob is depressed. The front 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.
3. 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 front 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 front 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.
4. 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 front washer pump/motor. If OK, replace the faulty front 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.
5. 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 front wiper relay (Refer to ELECTRICAL/FRONT WIPERS/WASHERS/FRONT WIPER RELAY - DIAGNOSIS AND TESTING). If not OK, repair the open front washer pump/motor control circuit between the CTM and the multi-function switch as required.