All relays on the engine fuse & relay box diagram have the pin numbers reversed on my '03 Tahoe...

[xDan]

Anyone else notice this? Did GM just mess this diagram up or what? Because every single relay in there works on my SUV yet they are all put in there backwards according to the diagram...and relays don't work if they are reversed.

 

[Rocket Man]

You're looking at the relays when they're turned upside down. Turn them over and look at the pin numbers from underneath and you'll see they match up.

 

[xDan]

I accounted for that. Either the diagram is wrong, the relays are stamped wrong or the truck is wired differently. I have OMRON relays and I can clearly see the numbers. I could make a video to prove they are messed up.

 

[Rocket Man]

I accounted for that. Either the diagram is wrong, the relays are stamped wrong or the truck is wired differently. I have OMRON relays and I can clearly see the numbers. I could make a video to prove they are messed up.

A couple pictures would do, one looking at the relays from underneath and one looking at the fuse panel diagram. Or just one looking at the diagram; the relays are all the same. Mine are correct.

 

[xDan]

Well I haven't taken any pictures yet...but it turns out these mini 4 pin standard type relays CAN be reversed, or put in 180 degrees out because the control side is top left and bottom right and the power side is the opposite. When you flip them around the wrong way, polarity is reversed but control and power sides of the relay function the same...this is bad for any of the same relays that have freewheeling diodes on the control side, over time any of those type reversed will have their diodes burned out, and circuits that need that feature are sensitive in nature and vulnerable to relay de-energizing voltage spikes...I hope NONE of those relays are freewheeling!

 

[Rocket Man]

Sounds like someone was messing around with those relays on yours. I'm pretty sure if GM had labeled the fusebox backwards someone else would have mentioned it in the last 15 years since these came out. Still curious to see what you're talking about on yours. We have a saying here- pictures or it didn't happen.

 

[rockola1971]

Anyone else notice this? Did GM just mess this diagram up or what? Because every single relay in there works on my SUV yet they are all put in there backwards according to the diagram...and relays don't work if they are reversed.

After reading full through this whole thread up til now I understand it as you mean your relays are put in backwards and are NOT keyed so they can be installed only one way? Is that correct?
Ill have to go out and have a look at my K chassis (2) 03 Tahoes and 05 Yukon Denali.

 

[xDan]

Going to have to do a video when it is light outside, only got one good photo. I lied, ALL of the smaller relays are installed backwards except the fog lamp relay (and you can't put that one in backwards, its a 5 pin) and it looks like someone replaced that one. I'd have to do a video where you see me turn over the relay. From some photos, the relay schematic on the 4 pin 8567's show a freewheeling diode.

 

[xDan]

@rockola1971 the 7866 fog relay is supposed to be a 5 pin, you could reverse that one too but whatever 87a powers would not work. Although the 8567's do have freewheeling diodes, that doesn't mean that GM actually requires it on those circuits.

 

[rockola1971]

I see what you mean. 87A is a Normally Closed Contact. If you ohm it from 87A to 30 with relay in your hand you should read a dead short across those 2 terminals. If I remember correctly the "sockets" in the fuse box has a spot for the male terminal #87a in both spots (relay installed correctly OR 180deg out) within the fusebox housing. The pic of relay 8567 indeed does show a flyback diode on the schematic silkscreening on the relay housing.