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George H.
George H., ASE Certified Technician
Category: Chevy
Satisfied Customers: 18697
Experience:  GM Tech ASE Master Tech 15+ years
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How do you replace a wiper pulse module on an 89 Chevy PU

Resolved Question:

How do you replace a wiper pulse module on an '89 Chevy PU?
Submitted: 8 years ago.
Category: Chevy
Expert:  George H. replied 8 years ago.

Hello I will answer your question,


If you remove the three bolts and the connector that attach the wiper motor to the cowling in the engine compartment and lay the motor on the bench you will see two small screws that secure the cover of the pulse board cover. Open the cover and slip the board out ad the new one in. then put it all back in the truck. The new module comes with directions. Part#88136


Its a piece of cake

Customer: replied 8 years ago.
I have removed the 3 screws, but the unit, although loose, is still attached to something on the other side of the firewall. It has to be the wipers somehow, because they move when the unit is moved, but I can't get it far enough away from the firewall to see how it is attached. I have not pulled hard on the unit/motor, because I don't want to break anything.
Expert:  George H. replied 8 years ago.



Can you just undo the module?

Customer: replied 8 years ago.
I will check right now.
Expert:  George H. replied 8 years ago.

Or is it this type?



Customer: replied 8 years ago.
It is the first type. I was able to get it loose from the motor, but the motor is still stuck to the firewall. If I can replace the module without removing the wiper motor, that's fine with me. The motor seems to work just fine, but only in the 'fast' position.
Expert:  George H. replied 8 years ago.
Yes if you just replace the module you should be OK. Bolt the motor back down
Customer: replied 8 years ago.
My module I have removed looks different than the replacement modules available at the auto parts store, and the ones available online. Mine looks like the one in the first diagram you posted, while the only ones available at the store look like the 2nd diagram. Is the 2nd designed to fit on the same motor as the first, or do I have to have the same pulse module, or get both a pulse module and motor? I am going to accept your next answer, and do not think I will need to bother you again about this matter.
Expert:  George H. replied 8 years ago.

Depending on which wiper motor you have I show two dorman boards a 906-136 and a 88136 that I cant tell apart by the pictures and both are speced for your truck.


Im afraid you are going to have to get with the part store and match your module to what they have in stock.


OEM p/n #12463090 If you have the second type check the connector and see if it matches your old one If it does it should work.


Do you have the number off your new module? Maybe a side by side picture of the connectors? I will see what information I can get for you

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