wipers not working

[markko]

Hi everyone, I just figured out that the wipers are not working in my 1978. The relays I installed last year are getting power, but nothing happens. I don't think the mechanism is seized up. At least the motor is not making any sounds like it is trying to move the arms. Is this likely the motor? Are there other diagnostics I should pursue before getting a new motor?
Thanks,
Mark

[spider2081]

The relays I installed last year are getting power,

I do not have a wire diagram for the relays you installed. I think the relay needs power on power on one of the relays coil terminals, either pin 85 or pin 86 . The other coil terminal should be ground. Battery voltage should also be present on both of the contact terminals, terminal 30 and terminal 87 for the wiper motor to powered. Isn't one relay for the slow speed and one relay for the fast speed? If so power to the coil would depend on what speed the wiper speed switch is in.

Do you have a wire diagram of the relays?
Do you have a volt meter to measure voltage?
Power for the relay comes from fuse B (2)

[markko]

Thanks for your reply. Perhaps I wasn't clear: the wipers had been working with the relays since I installed them a year ago. The wipers only just stopped working. Because the relays are getting power, I assumed that the problem was downstream of the relays. So, is there anything else to consider besides a faulty motor?

[TX82FIAT]

I would suggest pulling the cowl and testing the voltage pre motor after the relay to isolate where the problem is. If the motor has power check to see if the motor turns when unhooked from the linkage. The linkage is notorious for binding on these. If this linkage was bound it could have burned out the motor or even heated up the relay to failure.

[spider2081]

Because the relays are getting power,

What pins an the relay have power? Also isn't one relay for slow and one relay for fast speed?
Does a relay make an audible click when the wipers are turned on and when the speed switch position is changed from slow to fast or fast to slow?
How do you know the relays have power? Did you measure it with a voltmeter or test light?
I'm assuming you have the cowl removed if you are saying the relays have power. Is that correct?
Have you tried TX82FIAT suggestion?

[markko]

Well now I just feel stupid. I tried swapping the relays and nothing. I hooked the wipers up the old way, bypassing the relays, and they worked. I got everything put back together, and then noticed that the power wire to the alternator had come loose. Start with the simple, dummy.

[spider2081]

Old Murphy law of troubleshooting. "Its always the last thing you check that fixes the problem"
Bottom line, problem solved.