I installed a new multiswitch today because my right blinker had stopped working, and both wipers became erratic and were basically "fighting" eachother most of the time. After installation of the new switch the following seems to be happening.....

1. A soon as I start the truck, both wipers turn on and will not turn off until the truck is shut down.

2. The wiper fluid begins flowing and won't stop.

3. The hazards don't work.

4. The switch will go between dims and brights.

If I engage the hazards switch, however, the blinkers do seem to work. (Hazards still don't work) Wipers still turn on and do not stop.

I had the battery cable disconnected when I installed the switch. After having the problems I reset the computer, but it didn't seem to help anything.

Is there a certain reset procedure that needs to happen before the switch will work correctly? Was I supposed to install the switch connectors in any particular order?

Thanks.

 

The only symptom you described that has anything to do with the MFS is #3, but that's more likely a problem in the LCM.

Wiper arms moving out of synch is a MECHANICAL problem - not electrical. They sometimes loosen the nut on the shaft, so check that.

Wipers that don't park right is usually a motor fault, but yours don't seem to park at all. Considering the spray pump running constantly, these point to the WCM.

You don't need to disconnect the battery or clear the computer's memory to work on the wipers or lights, and doing that causes the engine to run poorly for a while, so try to avoid it.

Replacing any part is always the LAST step in diagnosis; not the FIRST. Next time, TEST the MFS.

 

Well I found the problem. Turns out the multifunction switch was good (good call steve83). It was the wiring harness that plugs into the mfs that was bad (loose wires). Ordered one from the dealer for $6.50. I guess I have a spare mfs for later.

Thanks.

 

What harness did you have to buy? I called today on the plug piece for the smaller one and they said it was going to be 18 bucks. I would rather replace he harness anyway, was it hard to change? it goes down in the dash somewhere doesn't it?

 

It's really just the plastic shell of the connector. The wiring harness was made SLIGHTLY too short, so if you tilt the wheel all the way down, it rips all the pins out of the connector. To fix it, get a new shell, pull the column shroud off, then PUUUULLLLLLLL the wiring to get a little more slack in it. Then transfer each terminal to the new shell.