pineapple_tree

I’m now realizing that owning a 27 year old vehicle is gonna come with lots and lots of electrical issues.

Okay. My CEL keeps coming on, and it’s for the A/C compressor relay open or shorted to ground. But I have no issue with the A/C not working like it should. It works perfectly, and my CEL light only comes on after a cold start, with the A/C off.

And that’s another story as well, that’s more than likely related to my code 33.

When I turn on the A/C, all of my gauges get drawn down. Fuel gauge, temp gauge, oil pressure gauge, and voltmeter. I’ve read about it drawing down the voltmeter because it’s not that accurate, but this hasn’t happened to be until I was trying to figure out what kept blowing the fuse for the A/C clutch.

I should note that the relay that’s in place of the factory one is one from a BMW, but it has the same pin layout as my old one. I don’t know why that BMW relay would be causing issues, but right now it seems that it might be.

I’ve checked my grounds visually and only one seems to be a little dirty, and that’s the dipstick tube ground. I’ve yet to test the resistance between there and the battery, but right now i’m aiming towards the BMW relay causing the code 33 and the gauge draw.

lawsoncl

Having the same pinout on the relay doesn't guarantee it'll swap. There are two main pinouts, and they swap the trigger and load pins. So that could very well be why your fuse is popping and the ECU thinks something is wrong.

pineapple_tree

Well, the blowing fuse problem was shorted back up lamp wiring.

But I got a new relay from Advance, and so far the code hasn’t come back, and my gauges are no longer drawn down anymore. Only the voltmeter gauge is still drawing down, but that’s likely because of a bad ground under the kick panel. I’ve yet to “improve” that ground.

So I guess that one relay was causing these issues. I don’t really know why, but i’m guessing even though the pins are the same, the internals were different and caused the PCM to freak out.

lawsoncl

Two pins are swapped depending on if it's a Bosch Type-A or Type-B. Swapping pins 30 and 86 means the load is getting powered from the circuit that would normally be triggering the relay.