1996 Volvo 850 GLT overheating MVSolved, bad new part

npharper · Post by **npharper** » 21 Jun 2012, 18:19

Yeah, I was worried about it burning up. Better to just leave it alone, as much fun as it would be to rig up the wiring and switch.

npharper · Post by **npharper** » 26 Jun 2012, 09:53

So I'm still waiting on the relay (apparently 3-day shipping for UPS means 3 business days, even though they ship 7 days a week--misleading).

Today, I had to move the car from one side of the street to the other for street sweeping. It started up fine, the coolant level in the tank was the same before and after, and it made the 1-minute drive without any noticeable losses of power or anything like that.

But, the "Check Engine" light is on. I hooked up my reader, which I've used in the past (it's the Torque app on an Android phone), and it shows no code. That seems bizarre to me. Should I try disconnecting the battery? Or might it reset itself once I get the relay in and drive the car for 20 miles or so?

This car was driving like a champ last week, so I really hope it's not totally shot now. Thanks again.

byeboy · Post by **byeboy** » 26 Jun 2012, 11:16

You probably could have gotten that fan relay from NAPA or Auto Zone...not a "Volvo Blue Bag" part, but if that makes you nervous, you could then have use it as a temporary, put in the Volvo one when it gets here, then save the local one as an emergency backup. The dealer might even have been not all that bad over the counter.

npharper · Post by **npharper** » 26 Jun 2012, 23:27

Boy, I wish I had. Neither O'Reilly or Autozone had the part, so I ordered it. It finally got here tonight. And it's not even Volvo brand. It's "German-quality" KAE brand.

But now I'm not sure if that was the problem after all. I got it installed, but the fan still doesn't come on. Not when I turn on the A/C, and not after letting it warm up to operating temperature. The fan works, as noted above, and the when I jumpered the old relay, it didn't work.

What could be going on here? Is it possible there is a fuse somewhere I'm missing? Or maybe a melted wire somewhere?

This sucks, man.

npharper · Post by **npharper** » 27 Jun 2012, 01:36

I hooked the fan straight up to the battery again, and it still works. When I jumper the new relay to the car, it clicks just like the old one, but the fan doesn't turn. Is it possible that FCP would send me a junk relay? Or maybe I'm doing the relay jumpering wrong in the first place. I started the car up, hooked up the outer two connections on the relay, and jumpered one (and the other, separately) of the terminals to the engine block with a wire. Is that the correct procedure?

npharper · Post by **npharper** » 27 Jun 2012, 04:29

I've been looking at a wiring diagram of the cooling fan system, which is entirely new to me. I think I figured it out pretty well over the last half hour, but please bear with me if I'm way off.

Since the fan works, I figure I can ignore the red and green wires that are clearly attached to fan (the same ones I bypassed to check that the fan does work). Since the relay is new, I will assume that is not the problem. That leaves the yellow and yellow/white wires of the middle connector (which appears to be tied to the ECM), and the single red wire of the other outside connector (which appears to pass through a fusible link, before turning into a green wire that connects to the starter motor).

Since I jumpered the prongs in the middle connector of the relay to the ground of the engine to test if it was working (which I believe was the correct procedure, I'm still waiting for confirmation of that), I'm assuming that the ECM turns the fan on by grounding whichever of the two prongs it needs to to get the desired fan speed, in basically the same way as when I jumpered them. Since jumping it did not get the fan going (in other words, there was no difference between when those prongs were grounded to the engine or plugged into the ECM), that makes me think that the yellow and yellow/white wires are not the problem.

So that basically leaves me with the red wire, which I think is the power wire, as a potential source of the problem. Does anybody know if this is, in fact, a power connector? Could the fusible link be the problem? Can I try running power directly from the battery to this wire or its connector on the relay to see if that makes the relay/fan setup work? How about using a voltmeter to check for the right amount of power (...which would be...)? Or do I have to start taking things apart to backtrack this wire's path to the starter motor and look for damage?

Or am I totally wrong altogether?

Thanks for all of your help so far. This forum is awesome. Way better than volvoforums for this problem, where not a single person has commented on my nearly identical post.

npharper · Post by **npharper** » 27 Jun 2012, 16:22

I'm seriously stumped here. Would appreciate any help.

BTW, after disconnecting the battery for a while, the CEL went off, so that minor problem is solved.

Anybody have any experience with a universal temperature switch for the fan? I'm thinking about maybe just bypassing all this complicated and expensive stuff with something like that, if it's a good idea.

npharper · Post by **npharper** » 27 Jun 2012, 17:24

I'm getting 12v though the red wire, so I don't think it's a power problem. Did FCP send me a broken relay?

Post by **precopster** » 27 Jun 2012, 18:15

The needle position on the temp guage b/w warm (85deg C and 105deg C) is only a smidgen above middle. Volvo did a really bad calibration on these guages.

Use your OBD device to give you ECT reading. At 105 deg C your fan should come on. To get it to 105 deg you will need to rev at 2,000rpm for around 2-3 minutes.

If not there is something wrong with wiring or relay or fan. As you've eliminated two of these there seems only to be wiring. Did you notice that with the KAE relay the rubber seal is so hard that it stops you pushing the connectors in properly? I had to fish the old brown seal out of my OEM relay and put it in the KAE.

Have you checked fuses?

npharper · Post by **npharper** » 27 Jun 2012, 18:34

precopster wrote:The needle position on the temp guage b/w warm (85deg C and 105deg C) is only a smidgen above middle. Volvo did a really bad calibration on these guages.

Use your OBD device to give you ECT reading. At 105 deg C your fan should come on. To get it to 105 deg you will need to rev at 2,000rpm for around 2-3 minutes.

If not there is something wrong with wiring or relay or fan. As you've eliminated two of these there seems only to be wiring. Did you notice that with the KAE relay the rubber seal is so hard that it stops you pushing the connectors in properly? I had to fish the old brown seal out of my OEM relay and put it in the KAE.

Have you checked fuses?

I did check all the fuses (twice now). I also did notice that the rubber seals were preventing me from pushing the connectors in all the way, but I tried it with the old seals and with no seals with no success.

I haven't used the OBD-2 reader to get the temperature, but I did rev it at 2,000 for at least 3 minutes trying to get it to turn on, and the needle did crawl above the middle of the gauge, but still no fan.

I tested that I am getting 12v to the power connector that plugs into the relay. And, as previously mentioned, the fan works when plugged directly to the battery. I don't think it's a problem with the ECU connection either, since I think grounding the individual ECU pins should have eliminated the ECU from the loop.

I'm thinking maybe a bad replacement relay, but that's pretty hard to believe.

1996 Volvo 850 GLT overheating MVSolved, bad new part

Re: 1996 Volvo 850 GLT boiling over/overheating