Wiper gremlin after sitting for a while.

[LaGuardia]

Hey, it's been quite a long time !
First of all, how's everybody doing ? My fault, I've been working abroad (Eastern Europe, setting up a new company there), and I almost forgot about my poor Eagle at home...

But now I'm baaaaack ! With this strange thing (I guess it's electrical, that's why I'm posting it here): after sitting for almost three months, yesterday I prepared for starting the car again. Checked the fluids, reconnected the battery, cranked the engine for 30 seconds and everything started ok. Fast idle for 2-3 minutes, hit the pedal, perfect idle...

Lovely !

Then this strange thing (when I stopped the car the last time everything I'll mention here worked perfectly): the volt meter needle starts trembling - "flickering" would be the right word if it was a digital thing - going rapidly from 7-8 to 10 to 14V and backwards. The interior lights and every other electrical item works normally, though.
Then, the windscreen wiper starts (the switch is in "off" position) just like if I turned it on in "delay" position. No way to stop it (the switch itself seems to be dead), it comes on by itself, a swipe each 10 seconds. Wow.

So I shut the engine off and I took a look under the hood: with ignition on, I can hear some random clicking sound around the wiper motor, but it seems behind the firewall, inside the cabin. The timing of the clicking noise is somehow related to the voltmeter needle movements. Then the wiper starts, and stops, and starts again.

While I write, I realize we must have some short there, but why ? And where do I start looking for it ?

I'm serious about electrical failures, so I decided not to move the car until I find out what it's all about: I disconnected the battery again and I'm using my bike right now. But soon I'll have to use the car and I must solve this thing. Any suggestions ?

Thank you all in advance !

[mudkicker715]

Do you have delay wipers? Meaning does the switch turn couter clockwise?

[LaGuardia]

Yup. I have them.

And it seems the wipers are stuck in "delay mode". But turning the switch (clock or counterclockwise) has no effect at all.

[Whuntmore]

Welcome back LaGuardia!

[LaGuardia]

I'm always here, even when I'm away...

[IowaEagle]

Welcome back.  I am suspecting the wiper delay module may be bad -- darn 30+ year old electronics anyway.  BTW Ford used the same part in many of their applications from that era.

[carnuck]

Unplg the box and see if it stops. Could be a rodent messed with your wiring while you were gone. Maybe the ground wire from the battery to the motor is good, but the one to the body is bad and it's backfeeding through the ground in the switch?

[carguy87]

I had this very issue on mine and took forever to find out the problem. Mine might have been a little different, once I turned my wipers on they acted like yours, but would not stop until I turned the car off.  I chased it for days until I decided, what the heck, and tore down the wiper motor.  I found that a corner of one of the magnets had broken off and had caught on the edge of the windings and touched the next magnet, allowing constant flow once it started.  Very weird, but definitely check the ground for the switch and make sure it isn't shorting to your voltmeter.

[Whuntmore]

Welcome back.  I am suspecting the wiper delay module may be bad -- darn 30+ year old electronics anyway.  BTW Ford used the same part in many of their applications from that era.

Is this Ford part still available, and do we have the Ford part number?  Or even what it came on.

[LaGuardia]

Thank guys, I'll check it out next saturday. Sorry for the lame question, but where do I find the wiper delay module ?
Is it somewhere near the motor or near the switch ?
I opened the dash once to replace the instrument panel, and it's been quite a PITA... I'd be glad to avoid doing it again

But I'll do what I have to do anyway.

[IowaEagle]

The module is a black plastic box that is located inline in the wiper wiring loom at the switch and unplugs from from the switch and loom.  I don't have the part number.  It is found on Fords that use a wiper switch similar to ours.  You need both the switch and box for conversions.  It may have been used on Jeeps too.

[carnuck]

Welcome back.  I am suspecting the wiper delay module may be bad -- darn 30+ year old electronics anyway.  BTW Ford used the same part in many of their applications from that era.

'88 F150 and no, it's not available new anymore. Ford just sells the non-pulse switch which goes in without the in-line box.
Is this Ford part still available, and do we have the Ford part number?  Or even what it came on.