Relay Identification and more...

Got an '89 Cherokee Limited, RENIX 4.0, AW4, and some things I can't figure out.

1 - there are 3 relays on the driver's side close to the front of the engine compartment. One is indeed the fan relay, but what are the other two used for? One is on the same block as the fan relay and one is on its own almost all the way in front (towards the radiator). When I connect and disconnect the one coupled with the fan relay, the other unknown relay clicks on and off, so they are somehow linked. I suspect that one of them is a home brew job, but on the other hand the Limited comes with all the bells and whistles acessories... I haven't seen these two relays anywhere in tech diagrams, pictures or in the parts yard.

2 - Finally fixed an annoying problem only to discover another one: Someone replaced the a/c cooling fan switch with a plug and hot wired the connector closed so that the fan ALWAYS ran when the ignition was on. So I reverted it to stock, and the engine immediately ran like garbage. Totally screwed up the fuel/ignition system. It stumbled, misfired, hesitated, and would flat out quit, but would start right back up. It would do this consistently whether at idle or on the freeway. 'Course the fan works perfectly! I then unplugged the temp switch and wired the connector back so the fan again always comes on with hot ignition, and now the damn thing runs fine like before. Everything I've learned about the RENIX system tells me that the simple a/c fan temp switch (not coolant temp sensor) should not affect the fuel/ignition system, yet obvioulsy it is. I wonder if it is connected to #1 above.

Thanks!

IIRC, the relays in question are for factory fog lights and headlight sentinel and are therefore tied together through the headlamp circuit. The one higher up on the fender well should be the sentinel and the one down closer to the radiator should be the fog lamps. As for the fan/ mixture issue, I'm not sure how they created the problem-- but it doesn't make much sense to me.

are you referring to these?

Thanks for the ID and picture. The fog lights were partially removed at some point, but the delay headlights are still working, so this makes sense. Found out today that the poor running is continuing despite wiring the fan back, so I guess it's just a coincidence that this happened at the same time. It's almost like the CPS or the fuel pump are weak, but is definitely a rather new replacement, and fuel pump sounds strong. Very frustrating because I thought I had just gotten the old trooper running good after TPS replacement, adjustment, etc. It feels like I need to try a new idle air valve, but this problem occurs at open throttle as well. However when at idle, it's more noticable because all of a sudden it starts acting like it doesn't know what to do, fluctuating 2-300 RPM and sometimes dying. My neutral start switch needs cleaning because it won't crank in neutral and the reverse lights are out. Would this cause it to die while running down the road, too?

Just to come full curcle and maybe provide a simple fix: replaced fuel pump relay and everything works fine so far. Come to think of it, I thoguht I had heard a relay clicking on and off that morning the problem with the rough running started. What an easy fix to a seemingly complicated problem :dunce: