rear wipers

[82Stang]

1998 Ford Windstar 146K mileage

I replaced the rear wiper motor with a newly rebuilt part and still no work. I put my test light on the motor terminals and got good ground. But when I turn the rear wipers on, no work. I checked the fuses, they are all good. There is a box under the hood, but I don't know which relays are for the rear wipers. This is really bothering me. Does anyone know how I can troubleshoot this little problem?

Thanks.

[serge_saati]

The rear wiper relay is the one at 2nd row, 1st column (left side). It's the gray square.

When you turn on the rear wiper, do you have 12V on red wire of the motor?

If not, it can be also the GEM (generic electronic module) that cause the problem.

If you have 12V, disconnect the red wire, and test current with ampere-meter. Sometime the motor is stuck inside. Check also the shaft of the motor.

Does the rear wiper washer works?

[82Stang]

Originally Posted by serge_saati

The rear wiper relay is the one at 2nd row, 1st column (left side). It's the gray square.

When you turn on the rear wiper, do you have 12V on red wire of the motor?

If not, it can be also the GEM (generic electronic module) that cause the problem.

If you have 12V, disconnect the red wire, and test current with ampere-meter. Sometime the motor is stuck inside. Check also the shaft of the motor.

Does the rear wiper washer works?

I havent done anything yet, but I can tell you this. The rear washer works. The motor is newly rebuilt, so that should be good, but I'll check it by hooking to the battery anyway. One thing I didn't realize is that the hatch is supposed to be closed in order for the wiper to work. I tried this, but still not working. I want to check the wires coming in from the tailgate, but honestly if the wires were bad, I wouldn't get good ground, right and power to there? I'm thinking maybe a relay, but not sure how to check that. Anyway, stuck up in an s10 blazer run rich, fuel inside intake issue first. Any ideas of what to check for the rear wiper, I will do. Just let me know what you think I should try first.

Just for FYI, if it is the gem how do i tell? And where is it?

[serge_saati]

Originally Posted by 82Stang

I'm thinking maybe a relay, but not sure how to check that.

The relay is very easy to test:
Remove it.
Connect the 12V battery to the coil of the relay (you have schematic under the relay). Use aligator clips for that
You should ear a click when you connect 12V
Just to be sure, check continuity in relay switch when it clicks.

The GEM is located inside the car under steering column at right. Opposite side of fuse panel. It's a black module. It looks like a remote starter module.

It's complicated to test it, but if relay is good, there's an indirect way to see if it's working or not.

Remove the relay, connect a jumper wire on the relay switch input pins of the distributor box. I mean where the relay switch is supposed to be connected when it cativate (not the default mode).

Then press wiper button. If wiper work, then the culpirit was the GEM or a bad wire connection (very rare). Or the wiper switch is bad.

To test the rear wiper switch, test voltage on pink/black GEM wire when button is pressed. You should have 12V.

Of course, when you do all these test, put the key in acc. mode. It use less current than ON.

[82Stang]

Originally Posted by serge_saati

The relay is very easy to test:
Remove it.
Connect the 12V battery to the coil of the relay (you have schematic under the relay). Use aligator clips for that
You should ear a click when you connect 12V
Just to be sure, check continuity in relay switch when it clicks.

The GEM is located inside the car under steering column at right. Opposite side of fuse panel. It's a black module. It looks like a remote starter module.

It's complicated to test it, but if relay is good, there's an indirect way to see if it's working or not.

Remove the relay, connect a jumper wire on the relay switch input pins of the distributor box. I mean where the relay switch is supposed to be connected when it cativate (not the default mode).
Then press wiper button. If wiper work, then the culpirit was the GEM or a bad wire connection (very rare).

If it doesn't work, the wiper button can be fried. Test voltage on jumper wire when button is pressed. You should have 12V.

Of course, when you do all these test, put the key in acc. mode. It use less current than ON.

Just for clarification, left is driver side. But 2nd column is? Looking which way. From in front of hood or inside car? Thanks.

[serge_saati]

Ok, the relay is located in the engine compartment fuse/relay panel. It's the black rectangular cover in driver side (just next the battery if you have 3.8L engine).

That's what I mean by "2nd row, 1st column" in relay section (bottom):



I alway count rows from the top, and columns from the left when I face the car. It's less confusing.

[82Stang]

Originally Posted by serge_saati

Ok, the relay is located in the engine compartment fuse/relay panel. It's the black rectangular cover in driver side (just next the battery if you have 3.8L engine).

That's what I mean by "2nd row, 1st column" in relay section (bottom):



I alway count rows from the top, and columns from the left when I face the car. It's less confusing.

That is an excellent picture. Thank you. It can get confusing when talking positions on a vehicle because different people look at them differently. For example, I am used to working on them and referring to them with the view point as if I were inside the car. So the left would be driver's side etc. Some people refer to it standing in front of the vehicle, which is why I always ask because it could be totally right or totally wrong. Anyway, I'll post back another day with some updates. Again, thanks for the picture.

[82Stang]

Originally Posted by serge_saati

Ok, the relay is located in the engine compartment fuse/relay panel. It's the black rectangular cover in driver side (just next the battery if you have 3.8L engine).

UPDATE:

Great news, for me, that is. I had installed a new wiper motor because the old one was frozen at the shaft and after revamping it, it just stopped working. I put the new one in and it still didn't work so I went back over what I looked at, checking for power, ground etc. All looked good. I checked the relay, like you mentioned, switched it with the fuel pump relay and VOILA! It worked. I read somehwere that others had the same problem with the relay not sitting right in it's plughole or that the wiring of the fusebox/relaybox itself was not of the best quality. Anyway, it's a common thing for these I read. And now it works. Thanks for the mention about the relay. I was thinking before to check it, but didn't know which one it was nor did I know about the issues Ford had with the relay not sitting properly. Knowledge helps when trying to decipher these things. I Appreciate the relay picture, it helped greatly.

Merry Christmas and happy New Year!

[serge_saati]

It was a very simple repair. I was sure it's a small problem.

[82Stang]

Originally Posted by serge_saati

It was a very simple repair. I was sure it's a small problem.

Unfortunately, it's usually never this easy.