1987 Ford Ranger XLT - Windshield wiper Motor debug

[kevinsteward]

After purchasing the truck I noticed no motor in the fluid reservoir.

1) Purchased new motor and NOS dual fluid reservoir.

2) Verified that when you actuate the washers, I see 12V on the BLK/WHT line (relative to GND)

3) Using an external power supplly set to 12V and 1A I can turn on and off the new motor.

4) I verified that the sprayer nozzle is gunk free and can pull water through it

5) Verified that I can blow water through the hose.

6) But once I solder the BLK/WHT and GND to the motor it will not turn and produces 0.4V at the solder connection (solder joints are good)

7) Looks to be a 6A c.b. fuse that read 0ohm across the leads when pulled.

Do I just buy a new fuse and cross my fingers again?

Any help would be appreciated as this just consumed the afternoon debugging (and I thought this one was going to be quick and easy)

 

[franklin2]

Make sure to the leave the motor soldered to the wiring when you are doing your testing. You have a poor connection somewhere in this circuit, you can't do any testing unless you leave the load of the motor on the circuit.

I would get to the switch and find the black/white there. Get your meter hooked up and then press the washer and see what voltage you have with the motor hooked up.
If you have 12v, then you have a connection or wiring problem from there to the motor.

If you do not have 12v, then it is probably a bad switch, since the power feed according to the diagram below feeds the wiper motor and the washer motor. You said the wiper motor works correct?

 

[kevinsteward]

Yes - wipers work well

 

[Curious Hound]

FYI a good fuse should read 0 ohms. That means it has good continuity and will conduct electricity. As mentioned, the same fuse serves the wiper motor. So, if the wipers work, the fuse is good.

 

[kevinsteward]

I see from the wire diagram that the Interval "windshield wiper washer switch" AND the "internal governor" both control the BLK/WHT line.

DUmb question:
Are the "windshield wiper washer switch" AND the "internal governor" both in the steering wheel column in the cabin, or in the engine bay after the firewall? (Sorry, never worked on a Ranger before)

 

[Curious Hound]

No. On your model, the governor should be a separate box mounted up under the dash near the steering column.

The governor is the electronic timer that controls the delay function of the wipers for when you just need them every 5 or 10 seconds for fog and mist and to tell the wipers to wipe a few times after you activate the pump. The governor doesn't actually control the pump. It just senses when you activate the pump.

 

[kevinsteward]

Thank you

So for the "windshield wiper washer switch" I removed the steering column trim to access it from the cabin?

 

[Curious Hound]

Thank you

So for the "windshield wiper washer switch" I removed the steering column trim to access it from the cabin?

That should get you there.

 

[kevinsteward]

Thanks again

 

[Brain75]

if you use your multifunction to trigger a wash and it wipes twice and parks, parks when you shut it off, and does intermittent then the govenor is 99.9% verified, and you can eliminate the troubleshooting there - it (the interval govenor) is a box way buried inside the dash that is hard to get to.
(I just suffered this on my '90 - washer worked and low but that was all - no park, courtesy wipe, etc).

I'd bet you have a bad connection (depin/loose pin?) going into your multifunction. (the stalk on the column that does everything - flass to pass, high/low. wash, wipe, intermittent, etc - everything).

 

[kevinsteward]

And the multifunction is at the column right? Not buried inside the dash?

 

[Brain75]

yes, the stalk on the column that does "everything"

 

[kevinsteward]

thanks all - I really appreciate the quick and informative feedback. Something to work on next weekend.

 

[kevinsteward]

I removed the connector to the stalk that has the wiper washer (when you pull it)
Strangest damn thing, I am monitoring the pin that connected to the BLK/WHT wire and then my ground is the GND to the BLK that connects to the motor as ground - and now I see nothing at the stalk!!

Last week without opening up the column and the BLK/WHT andBLK that we in the engine bay and not connected to motor was outputing 12V

This may enduo a truck that does not have washer capability lol

 

[kevinsteward]

I took the stalk off the column and started to ohm out.

Looking at the stalk pic
The upper left is where the BLK/WHT is connected
The lower left is wehre the RED is connected <- assuming when all connected up this is 12V ???

When I attached an ohmmeter to those two pins and pull the stalk I read 130-250 ohms

Should this be a short 0 ohms or is this resistance when pulling expected?