'98 V70 Fan Not Running in Low?

Post by **bmdubya1198** » 21 Jun 2018, 17:34

I decided the other day to swap the fan in my GLT with the fan out of my 2000 R since I was thinking about someone's previous suggestion that it could have something to do with the intermittent "hiccup." The more I thought about it, the more it made sense (only happens in stop & go driving when engine is hot, doesn't seem to happen with A/C on).
Anyway, after swapping it, I've noticed that when I get home and turn off my A/C, the fan turns off immediately. Usually it will continue to run after turning the air off (I usually let the car idle a couple seconds before turning it off) but since I swapped the fan it doesn't.
I had changed the relay a couple months ago because I thought that may be the issue (fan wasn't kicking on with the A/C) but since replacing that relay, everything has seemed to work normally and the fan came on as soon as I turn on the A/C. My only concern was that the fan was only functioning in one speed, which is my reason behind swapping it out.
The fan definitely has a different tone than the old one, and I don't know why.

Unless there's an issue on the car's side, both fans seem to work perfectly fine. I tested the fans with a jump box on both low and high speeds and they ran fine.

The car hasn't run hot or anything, it's just a little concerning that the fan isn't running, because the engine is certainly hot enough for it to run. And it may just be placebo effect, but my A/C has felt warm. Then again, the charge could be low (compressor appeared to be leaking a while back) and it's been 95 degrees the past week.

Anyone have any ideas here?

Post by **jimmy57** » 21 Jun 2018, 17:48

Check that the terminals in the grey two wire connector on relay are plugged onto the relay pins. The plastic on the bullet style connectors disintegrates and then the wires are not installed when the grey plastic connector latches. The terminals will stay if squewzed a faint bit and then the wires are pushed onto the round pins on relay. Those two are the hi and lo speed wires that ground the relay for the to speeds. The relay could be the issue but terminal problems with age has been far more common on ones I've seen with that fan issue.

Post by **bmdubya1198** » 21 Jun 2018, 19:03

I repaired the connectors on the two yellow wires with the bullet connectors a while back, as they were completely disintegrated. Everything else seems good, but I'll double check all of those connections.

Post by **Ozark Lee** » 22 Jun 2018, 07:47

You can ground the relay side of those connections, one at a time, and check the function of the relay itself. One will turn the fan on low and the other will turn it on high if the fan and relay are functioning properly.

...Lee

Post by **bmdubya1198** » 22 Jun 2018, 08:17

Ozark Lee wrote: 22 Jun 2018, 07:47 You can ground the relay side of those connections, one at a time, and check the function of the relay itself. One will turn the fan on low and the other will turn it on high if the fan and relay are functioning properly.

...Lee

Makes sense... so I ground the terminals at the smaller gray connector, like Jimmy mentioned?

Post by **Ozark Lee** » 22 Jun 2018, 13:17

Actually you ground the pins on the relay itself, one at a time, where the connector with the yellow and the yellow/white wires plug in, Don't ground the red wire or bad things will happen. Getting that connector loose is tricky and I find it easier to remove the relay with the wires attached before you try. It just snaps into the groove on the radiator shroud and a firm tug will get it out.

You can do it key off and the fan should work since the relay is always powered from the battery. If that works on both speeds then it points to a wiring problem from the ECU to the relay and the most likely failure point is the connector itself.

...Lee

Post by **jimmy57** » 22 Jun 2018, 14:20

The yellow and yellow/white connections are the pins the ECM applies ground to to control the hi and low power feed to fan. The relay is not controlled on 12V side, it is ground controlled.

Post by **bmdubya1198** » 22 Jun 2018, 20:13

Yup, that's what I meant about grounding the pins, just making sure I was thinking of the right ones. Tested that earlier today, and the fan works perfectly fine.

When I got home just a little bit ago after turning off the AC, the fan turned off like it has been doing. But before shutting the car off I looked at Torque on my tablet and saw coolant temps up to 204 Fahrenheit. If I'm not mistaken, the fan should have been running.

I think there is probably some sort of issue between the ECU and the relay. That'll be the next expedition...

Post by **abscate** » 23 Jun 2018, 03:56

Somewhere I documented when my fan came on and off but I think it was over 100c, so I’m not sure 204 is enough to trigger the fan

Post by **bmdubya1198** » 23 Jun 2018, 07:49

abscate wrote: 23 Jun 2018, 03:56 Somewhere I documented when my fan came on and off but I think it was over 100c, so I’m not sure 204 is enough to trigger the fan

I can't remember when it came on before, but I remember watching it at one point a while back. I'll have to search around on that and make sure it's coming on when it should.