[OldGuy]

Sorry for the confusing title, but to say my wipers only work on high speed would be incorrect. The low speed is not working, however, my wipers work at all settings. When they are on delay, they work perfectly, but when they cycle on, it's a very fast swipe across the windshield. If I move to low speed and high speed, the wipers work fine, but they're always at high speed. Sorry if this is still confusing, but hopefully someone here has had the same problem and will understand what I'm trying to describe
Thanks, guys.

 

[Kenzen]

This is a weird one...hmmmm.....digging into the tech manual the "wiper 2" relay controls if the wiper goes fast or slow. Try swapping or replacing that one.
Ken

 

[Kenzen]

Digging a little more, the power connection to relay wiper 2 (which is # 63) has a diode between it and the power going to wiper relay 57, aligned so that power to 63 will also power 57, but power to 57 will not energize 63. (The power comes from the BCM.) If this diode shorts closed, relay 63 will always energize and make the wipers always run fast.
Ken

 

[Kenzen]

...and the diode is in the fuse block.

 

[OldGuy]

I sincerely appreciate your response, but I'm lost. History, the cruise control and wipers/washers stopped working. I figured the multifunction switch was bad, so I grabbed one from a U-Pull lot. The cruise control started working, but still no wipers. I connected test leads to the battery and all worked correctly. I started assuming that the BCM was bad, but in he back of my mind, I considered the possibility that the used part I got may have been somewhat better than mine, but it could still be the reason for the problem. After pulling the steering wheel and wrestling with those nightmare clips to get the air bag out, I was not really anxious to perform that task again. After constantly coating my windshield with Rain-X and having to pull to the side of the road in some really bad downpours, I broke down and ordered the $150 multifunction switch and replaced. Then wipers worked, but always on high speed.
The relays you are referring to, are the numbers you give the location in the fuse box? Basically, if I replace both 57 and 63, I should eliminate all possible bad parts except the BCM, correct? Since the truck runs great and everything else works as it's supposed to, I feel pretty confident that it's not the BCM.
Thanks so much for your response! Have you ever replaced one of those switches on a Colorado/Canyon? It's a nightmare! I've replaced several of those switches on other vehicles and most mounted to the side of the column. Only one other one required removing the steering wheel, but it did not have the stupid little access hole to somehow magically activate those 4 clips when you have absolutely no idea where they are, how to depress them one you find them and there are no clear descriptions of what you are attempting to do completely blind to what's inside that little access hole. I could get one or two, but working on the third one always re-locked the first two that I had released. I remembered that there were two small torx screws on the backside of the steering wheel that seemed to hold those spring clips in place, so I removed those and shoved a screwdriver in the access hole and broke them loose. I always grab a few spare parts when at the U-Pull lot, so I knew I had replacements to put it all back together, including a spare steering wheel if needed.
Thanks again. I'm happy to have wipers again, but I'll be happier when they are completely correct.

 

[OldGuy]

Just saw your third post. So, it's not necessarily one of the relays, but possibly the diode, huh? So that would be inside the fuse box, or is it something that is on the surface? Either way, do you have any idea what it would look like? Will it be enclosed in something, or just be an inline soldered item?
For the third time, thanks so much for your help and taking so much time to dig into this for me. I was actually an electrical engineering major in college, but the schematics they have out there these days are nothing like what we learned in college. Not near enough notations and the ones I find have numbers that apparently denote the wire color, but the key for those numbers never seems to be included. Simple little notations that we learned in class just don't seem to be used anymore, and I'm an old dog that is not really interested in learning new tricks!!!

 

[Kenzen]

There's 2 diodes in the fuse box. They are the same size as the fuses, but black and have a diode symbol on them. (A solid triangle with a line across the top point of the triangle.) I haven't figured out which one is for the wiper, but I recommend you swap them to see if the problem moves. DON'T lose track of the direction they point - take a picture of them before you pull them - I'm not sure if the connectors are polarized so they will only go in one direction. (BTW, I'm a EE also, but jumped to software during the dot-com boom. But my real training in all of this was from the Navy, and growing up building Radio Shack electronic kits.) Also, going on memory, the multifunction switch grounds at the passenger side ground splice pack under the hood. If you haven't cleaned up that connector, I recommend doing so.

And thanks for letting me know to avoid replacing the mulitfunction switch - I've done it on another vehicle and it wasn't fun.

 

[Kenzen]

Diode 64 is for the wiper. Diode 65 is for the A/C clutch.

 

[OldGuy]

Fantastic info! I do remember seeing somewhere about the diodes in the fuse box and that one was for the wipers. I think I swapped the two to see if that was the problem before replacing the switch. I bet I just have it in backwards. I loved those Radio Shack kits! If you learned in the Navy, I'm sure you got much better training than a college course. I'm sure your training was accompanied by a lot of hands-on experience. Thanks for your help, and much more importantly, thanks for your service sir!!

 

[Kenzen]

Thanks OldGuy!

 

[OldGuy]

You 'Da Man! The diodes are polarized and mine was noticeably sticking up a little from the rest of the fuses and stuff in the fuse box. I had apparently put it in backwards and it didn't go in all the way. Pulled it out, turned it around snapped it in and all is well!
Thanks again!

 

[Kenzen]

Yahoo!!!!

 

[lens20v]

Not sure if this will help.but when my BCM went bad I saw the windows not working. The local mechanic admitted that he could not fix it. The dealership was able to fix it but it wasn't cheap. No problems since then.