Author Topic: Help Article: Wiper Motors and bench testing them.  (Read 1829 times)

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Help Article: Wiper Motors and bench testing them.
« on: April 02, 2020, 08:00:08 PM »
Help Article:
                Wiper Motors and bench testing them. 

Every so often we have illogical returns or complaints  about certain brand new or U.S. reliably rebuilt parts not working.    One such part is the GM series of wiper motors based around 1968-84 various models that are returned..., not parking, not starting,  DOA..    brand  new parts.. they're checked & pretested at the US assembly point.. often genuine re-manufactured etc..

A thought to keep in mind if you get one..... regardless of were, who or how you get one ... new (if made) or reco or ex a mates junker etc etc....... don't just "bench test"  a wiper motor it by .. sticking a wire here or there. .... don't try to figure out the "irrelevant fact"  that some come with  3 wire terminals & another 2 .... or 4.. by touching a wire here or there & hoping somehow.... it will pop out & magically with multiple speeds & auto shut offs working etc etc.

We also had a very unhappy fella with a brand new window motor at our door at 9 am.. p#ssed off & claiming similar.. claimed DOA expletive etc etc.... but he had put a + & - on the 2 Up / Down terminals at the same time.......  Luckily it did not fry (that particular window motor needed a body earth & single power up or down only) & we powered it up correctly and he left. Lucky it was not a wiper motor..etc.

Just like household electricals.. they're so unforgiving.. be careful out there.  Maybe buy a good digital multi-meter and watch a few videos on how to skill up and use it well.
..... make sure your wiring is right.. your cars earths are strong..before you buy one.  Could it be a burn't out wiper switch??  maybe its one with AUTO PARK ? ..  ...and make sure IT works too..    don't stuff up pulse boards etc..

Get hold of a wiring schematic or look up youtube  (see a linked image to type in below for your help)  for a test  demo for  that most common type of GM wiper motor..? and google wiper diagram IF you need to test a new one.. if you do .. ask why...first.. before "testing it"...
Attached is a link to a vid test proceedure if this helps anybody out there.

We don't know everything but do know like you do.. that It's far too  easy to wreck good electrical parts   and certainly after being cross wired, especially on a converted dash or home made fiberglass mounts etc....  they will NOT WORK.


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