On the 89 I recently picked up, I have done some searching on the sight on no wipers, the question I have that I have not found an answer to is will the wipers work if the little control box is unplugged?
Do the grid heaters have their own temp. sensor to energize them or do they work off the eng. coolant temp. sensor?

The fuse box in this unit is just hanging down below the steering column, for the life of me I can't figure out what it attaches too rather than just hang there right above my feet?

Thank You!

 

Is the wiper motor working but all the bushings on the linkage rotten and the linkage fallen apart?

The grid heaters on a '89 are controlled by the black box just a little bit bigger than the size of a deck of cards near the steering column on the firewall.

The fuse box attaches to the small panel under he steering column of the truck.
Take it off by removing the 4 Philip head screws. One side of the fuse box has a notch that fits into a slot on the panel. The other side of the fuse box has two round nubs that click into the panel on the other side.

Those panels that the fuse box click into are often broken as people do know how to use them correctly and they get brittle over the years.

 

Oliver, no the wiper motor does not seem to be working, I have tried working the wiper arms to get it to work but it will not, fuse is good. I will test for power at the motor this week.
By the way, Thank You again for the shroud and intake pipe you hooked me up with!!!

 

Don't forget, they need a good ground, more than once I have messed with them for what seems like an eternity to find a poo ground was the issue........

 

The Grid heaters work on a separate air temp sensor in the intake air.

My fuse block was just hanging also as it had broken snap tabs. I used tie-wraps to hold it to the plastic plate after drilling hole(s) in the plate. Then the plate attaches to the dash with 4 flat head philips screws.

My wipers worked but only on high speed. The intermittent wouldn't work even though the box was in place. I took out the box and tested it's components so no reason it wouldn't work. I found a broken connector to the box and after not finding a new connector I cut it off and soldered the wires directly to the circuit board of the wiper box. I do not know if the wipers will work with the box unplugged since only one connection in the plug was broken. If you have the Factory Service Manual with the wiring diagrams they are very good and will show how the wipers etc... are connected. The FSM is a .pdf which I put up on my server here. https://remote.freeholdconsulting.co...utyTruckSM.pdf

Hope this helps.

Edwin

 

So the fuse block is supposed to be mounted to the dash colored panel held on with 4 screws directly below the steering column? It seems kind of flimsy to hold the fuse block.

Thanks all for the replies!!!!

 

That is it.
It does work, but I have seen a lot of broken, warped or cracked ones over the years.

 

I finally got around to pulling the inoperative wiper motor, it's open ohm's wise from the center two spades (high/low speed) to ground so, motor is bad. In the process of pulling the motor, attempting to get the linkage off the ball on the lever bolted to the motor, the plastic joint disintegrated, can a person buy the plastic piece?? I attempted a search for wiper linkage here and came up with nothing. Thanks for the help!!!!

 

Yes the plastic bushing on the wiper arms can be bought new.
The auto parts store versions are not a good as the original ones, but the original ones are all pretty brittle nowadays.

 

When you do the plastic bushings, disconnect the 6 bolts, 3 on each side, that hold on the turny thingys (I don't know what they are called, the shafts with the splines) and remove the entire assembly through the slots in the body. Trust me,it is almost impossible to get to some of the bushings while it is in place. You may as well do all of them and keep a box of the bushings in the truck, for when they fail again...Mark P.S. use a pair of channel locks to install them...

 

Wiper motor has bad spots in the armature I guess so I'm going to replace it, HOWEVER there seems to be a month break when ordering a motor for an 89, the pictures shown on the parts store sights say the pictures they show are not the actual picture (great) and they ask for build date, easy peasy, walk out to truck, look at door post tag and all is well ACCEPT, NOTHING inked into the tag is readable. GVW blank, Vin blank, date of mfg. blank. Is there any way to know build date so I can order a motor online? Thanks!!

 

That stupid label they put in the door jam is like a carbon copy of something and the numbers rub off after about 20 years or so. Mine was completely clear and I had to get the frame looked at by the CHP before I could get it titled in CA. What a PITA.

I looked in my Service Manual for some clue as to build date but it only breaks the VIN down to year, etc... No month or day.

Edwin