seadevil3

Have a 97 xj and the old motor didn't work sense I bought it. I finally ordered a new one, installed it on the wiper frame, and plugged it up. I didn't install the frame back in it yet as I wanted to see how well and if it worded. Well turns out that it works on slow and high, only worked for like 10 seconds and then it stopped working and now it hums when I turn the wiper lever up. Even with the jeep on it still just hums. I checked for voltage going to the motor and I get anywhere from 10.6-11.3 volts. Do I need to replace my lever or does the wiper frame have to be installed for a ground? I'm confused and stuck right now and just need a check list of what it could be please.

Jim Malcolm

Do you have the ground strap "connected"?

seadevil3

What strap, the only grounds are o the new motor it has a ground to the body of the motor. When I pulled the old one off, still has the rubber sock on it but the only ground that was on that was the bolt that bolted the mounting wiper arm frame to the actual body. There wasn't external strap.

Jim Malcolm

I was referring to the "main" ground strap that goes from the engine to the firewall. Other than the small wire connected to the PS inner fender, that ground strap from the engine to the firewall is the ground for anything mounted to the body... Wasn't sure if maybe you removed it and haven't yet reinstalled it, limiting the ground path for the motor.

seadevil3

Yes, I actually upgraded the wires to the "big 7" wires but what's PC ground. Where is that? I'll check that tomorrow

Jim Malcolm

PC ground? Where are you seeing that?

seadevil3

Small wire connected to the PS inner fender, I'm throwing a blank at what PS stands for lol

Jim Malcolm

passenger's side... The negative battery cable assembly has a small wire that connects to the passenger's side fender well. From what I can find, the wiper motor grounds through the connection to the driver's side fender well, next to the ECM...

Roler

Not exactly.
Due to that cable between batt neg and inner fender, the entire body actually becomes a ground point...

seadevil3

Ok great thank you, when I did the "big 7" cable upgrade I think it got rid of that little ground cable but I'll double check grounds tomorrow and let you know. Thank you

Jim Malcolm

I understand what you're saying, but if you compare the, I don't know, 14ga wire on the below part to the braided ground strap, which do you think is actually passing more of the current... I always found the ground wire to the inner fender quite comical.

https://www.autozone.com/batteries-s...25b/570458_0_0

If you want to get extra, super technical, there should only ever be one connection between the battery and "ground". Consider for a minute what would happen if the main ground wire from the battery to the engine block were to fail. When you went to start the engine, the starter motor would ground through the braided ground strap and then through that tiny 14ga wire.

seadevil3

All my wires are 2GA wires now. Block to body, +&- battery, starter, ECT

awg

test both the old and new motors outside the car, connected to a good battery and see what happens

You may have either poor conductivity in a wire, or a corroded fuse/holder

Roler

True that the batt to fender cable would benefit from an upgrade. The braided strip and its actual function has been debated about a lot though on here...with opinions ranging from just for radio interference suppression to more important functions contributed to it...

cruiser54

As to the braided strap.

The field service engineers thought enough of it as a ground strap that they recommended refreshing its connection on the firewall to improve the ground path.