2002 Bonneville, wipers run intermittently while the switch is off. I've replace both the motor and switch and they were brand new parts. Seem to work for about 4 months, now it's back doing the same thing again. Is there a relay some where in the car that could be sticking?

Just replacing parts isn't the way to find the problem , viewing wiring diagrams an testing the electrical circuit with a DVOM - digital volt ohmmeter is . There are no relays involved . Do yourself a favor an take it to a qualified repair shop before you buy more parts that are not needed .

The only module that may be tied into the wiper motor is the body control module and failure rate on these is low. What are the symptoms? Wipers not working? Wipers won't park? Motor runs but wipers won't move?

When the windshield wiper / washer switch is turned to the OFF position while the wiper motor is somewhere in mid-cycle, the wiper motor module will continue to operate the wiper motor until the wipers reach the park position. If the ignition is turned off while the wipers are in mid-cycle, the wipers will stop immediately where they are. The wipers will park the next time the ignition is cycled to the ON position.

Schematic Reference: Wiper/Washer Schematics


1

Did you review the Wiper/Washer System Description and Operation and perform the necessary inspections?
Go to Step 2
Go to Symptoms - Wiper/Washer Systems

2

1. Turn the ignition ON.
2. Turn the windshield wiper/washer switch OFF.

Are the windshield wipers always on?
Go to Step 3
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

Disconnect the windshield wiper/washer switch connector.
Are the windshield wipers always on?
Go to Step 4 if yes
Go to Step 7 if no

4

1. Disconnect the windshield wiper motor connector.
2. Test the windshield wiper switch signal 1 circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
Go to Step 11
Go to Step 5

5

Test the windshield wiper switch signal 2 circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 11
Go to Step 6

6

Test the windshield wiper motor high speed circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 11
Go to Step 9

7

Inspect for poor connections at the windshield wiper/washer switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 11
Go to Step 8

8

Replace the windshield wiper/washer switch. Refer to Windshield Wiper and Washer Switch Replacement - On Vehicle in Steering Wheel and Column.
Is the repair complete?
Go to Step 11
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9

Inspect for poor connections at the windshield wiper motor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 11
Go to Step 10

10

Replace the windshield wiper motor. Refer to Windshield Wiper Motor Replacement .
Is the repair complete?
Go to Step 11
--

11

Operate the system in order to verify the repair.
Did you correct the condition?
The Wiper / Washer System consists of the following components:
?€¢
Windshield wiper / washer switch

?€¢
Windshield wiper system module / motor

?€¢
Windshield washer fluid pump

?€¢
Windshield washer fluid level switch

?€¢
Instrument panel cluster (IPC)

?€¢
ACC 15-amp fuse

?€¢
WSW 30-amp fuse

this tricky cause both ur wiper stalk and wiper mafuctioning can cause this ur wiper motor has a pulse board on it probrably be first thing to replace check out rockauto.com theyre the best and cheapest on parts

The problem is a broken part in the module which is inside the wiper motor. As far as I know, the part is not available, and you must replace the entire wiper motor to repair the problem

I am having the same issue with my 2003 bonneville. Changed out the control switch, no difference. Changed out wiper motor, still no difference. Seems that the problem may be on the wire for the delay. There is a constand 2.5 voltage when the switch is in the off position, cause the wipers to run intermitently. The wipers will run more often if you rev the car engine and increase the trace voltage. A wire is going to be added to bypass the bad wire in the harness. Crossing my fingers, hope this works.

try replaceing the circut board in the motor

If the wipers end up in the vertical position and they are the HIDE type usually its the park mechanism mounted on top of the wiper motor that the linkage attaches to, there is a small spring loaded lever on the bottom of this device that wears out and fails to activate the PARK position proccess when the wipers are turned off. When the wipers turn off the motor reverses and the lever is meant to catch on a tab and compress the mechanism pulling the wipers to the park position. Only thing I know what to do is replace this mechanism, ($150. new 25. used)

2002 Windstar wipers would come on by themselves, or not work set on intermittent, driver door lock would not work sometimes, ABS and brake light would come on sometimes, the problem was in the park switch inside the wiper motor. I replaced with wrecking yard wiper motor $44.95 w/13 month warranty. no more problem. check how many pins on connector plug, mine had 5 on the wiper motor side.Take the wiper assembly off of the metal cowl, 2 nuts, & I bolt, it is easier to snap the actuator pieces off of the wiper motor that way. God Bless JMR