Working on this vehicle for a friend.

Front wipers not working at all. Rear wiper works fine.

Wiper motor works fine when I connect it directly to battery. The 2 relays both have good resistance and both click when I connect them to battery. Fuse in engine compartment is intact. Based on all that I bought a multi function switch off eBay and put it in this morning. Wipers still don't work. All other aspects of the multi function switch appear to work just fine.

What am I missing??

thanks!
Chris

 

First, listen and feel to see if the relays click. If they do, meter the relay sockets. Make sure the ground pins are grounded, the power pins are receiving power, etc. I once troubleshot a Jeep fuel pump issue, finding that the ground pin on the FP relay socket was not grounded. It was an easy, cheap fix.

Good luck!

 

So I've finally gotten around to using a volt meter on the socket connections for the relays. I just don't know what I should be seeing from each socket. I get how the relays work but should I be seeing 12 volts from the socket for pin 3 (30) and pin 5 (87) when the switch for the wipers is on? Because what I'm seeing is the voltage going from 0v to 400mV over about 15 seconds and then resetting back to 0v and starting over again....which seems weird.

I pulled the box out to look at the bottom to see what condition the wiring was coming into the box and it all looks intact and clean. There aren't any wires coming directly into those relays. Below is a pic.the relays would be to the far right in the pic where the philips head screws are.

 

It's a 12 volt system. Everything should read either zero volts, 12-13.5 volts, or continuity. 400mv raises a flag that something is wrong upstream of the relay socket.

D