1978 280Z Windshield Wipers

[hornz]

My wipers only function in fast and slow speeds. They will not "delay" or park properly in the off position.

1) Are these problems related?

2) Is there a "delay" module located on the motor or somewhere else?

3) Is this situation repairable or will a new motor (or module) be required?

Any thoughts or suggestions would be appreciated.

[sblake01]

There is a relay in the passenger footwell. The one for the wipers is the one with two plugs and the contacts facing outwards. It however is most likely not the cause of the problem you describe which is actually two problems. The lack of the middle speed is most likely due to dirty or bad contacts in the switch itself and the parking problem is most likely due to dirty or bad contacts in the auto stop mechanism located in the center under the cowl. Do you have a FSM? Pages 59-67 in the Body Electrical section cover the wiper system and would be a bit lengthy to paraphrase here.

[TomoHawk]

I didn't know there was an auto stop mechanism under the cowl. Where would that be? I've had the entire wiper system out, and basically all there is under the cowl is the motor and the linkage arms. From discussions here & on HybridZ, the auto-stop switch is inside the wiper drive motor.

hornz-

You might first try cleaning all the connectors; on the wiper control amplifier, and the motor connector under the hood.

thx

[sblake01]

It is on top of the motor assembly. Here's a couple of scans:

[hornz]

Thanks guys for your information. I will look into cleaning up connector contacts and see how that works. I am relatively new to this site and enjoy coming here to pick up hints on maintenance and correction.

Hornz

[TomoHawk]

I had an  idea, that since many people are upgrading things to electronic control, would there be an advantage to just replacing the old, factory wiper amplifier module?  With all the 40+ year-old ignition modules I hear of going bad, I'm likely to believe that the electronics (transistors/semiconductors) inside the module could benefit by being replaced with a module built with the most modern semiconductors. 

You'd need to get an amplifier in working condition and reverse-engineer it, to come up with one that is an exact replacement, but with better semiconductors.

[TomoHawk]

I was unable to find a NEW wiper motor amplifier anywhere, and there were only used ones on eBoo.  Supposing your stops working completely, is there a way to bypass the amplifier to get something like the Civic motor  to operate?  I haven't thought of probing the connector to the amplifier since it's in a tight place.

Again,  a good alternative would be to rebuild the amplifier or design a new one that directly replaces the old ones.