12 replies to this topic

[Mugs]

2000 Impreza OBS

 

So here is what is going on. About 3 days ago my fan (for the heating-A/C) quit. I thought it was a fuse, but nope no fuse problems. I have no idea where the relay is located, and its always convenient that suby labeled their stuff SBF 1,2,3, etc, etc,

 

But the next day it worked again so I figured a fluke. But nope it quite today while in stop and go traffic and 85 degrees. Then about 4 hours later it works again.

 

Any thoughts on what might be going on. And where to start doing electrical testing. I hate electrical, so I feel very frustrated right now. 

 

Thanks all in advance. 

[1982gl4]

Does it not work on all speeds? I've seen the motors themselves fail. The brushes get thin, and stop making contact. If it dies out again, hit the bottom of the fan motor (doesn't have to be a super hard hit) Just enough to jar the brushes back into place and the fan will start up again. If it does start again it may need replacing. 

Edited by 1982gl4, 30 August 2013 - 09:12 PM.

[Mugs]

Does it not work on all speeds? I've seen the motors themselves fail. The brushes get thin, and stop making contact. If it dies out again, hit the bottom of the fan motor (doesn't have to be a super hard hit) Just enough to jar the brushes back into place and the fan will start up again. If it does start again it may need replacing. 

Tried that...yes when it works, it works on all speeds. If it didn't I would replace the rheostat on it, and call it a day, well hopefully. 

 

I wish the motor had been a hard failure, I could just apply power to it and see if it works. No work, replace motor, Done 

Edited by Mugs, 30 August 2013 - 09:47 PM.

[Rooster2]

I would advise removing the fan motor unit. I had an earlier Subie with same problem. Turned out crud from the louvers just outside the windshiled, and before the hood had allowed tree leaves and dirt to accumulate to the point of binding up the motor. Once I cleaned out the crud, the motor worked perfectly again.

 

Search this forum. There is quite a bit written about this subject, and how to clean out the crud. Pictures there too, I think.

[MR_Loyale]

Turn it on and try wiggling the connector where it plugs into the motor.

[Fairtax4me]

The blower fan relay is probably the least accessible relay in the entire car. It's buried in the top left corner of the dash, over top of the fuel pump relay and the main relay.

Next time it doesn't work, check for 12V at the fan plug. Normally there should be 12v on only one pin. But you will likely either have 0v on both pins, or 12v on both pins.

0V means its not getting power. Either the relay isn't being grounded, or maybe its just gone bad. Or there could be a break between battery power and the relay. The relay is grounded through the fan speed switch, so its only "on" when the speed switch is in an "on" position. The fan motor is also grounded through the fan speed switch.

12v on both pins of the fan motor plug means there is no ground path for the fan. This could be a break between the fan and resistor block, or between the fan speed switch and ground.

[Mugs]

Thanks, 

 

I had already pulled the 3 relay holder (Main, Fuel and ?) down earlier this summer when I replaced the blinker relay, and just simply tucked them over to the side in a safe pace behind the wire harness coming out of the fuse box. Thinking it would be advisable to leave them where I can gain quick access in case of a malfunction. 

 

So If I am reading you correctly, the fan relay is above that. I will look under there tomorrow, and see if I can find another relay. I'll also carry my DMM with me so that if it does fail again I can do the tests you recommended. 

 

Thanks again.

 

 

P.S.

I'm beginning to think I may have some electrical gremlins throughout the car. My driver side head light keeps "burning" really dim, and doesn't t get brighter with the high beams either. I replaced the bulb and it lasted like 2 weeks before doing it again. 

 

I'm getting pretty frustrated, with this whole thing. A car payment on a new car is looking pretty tempting. I can't afford not to be able to go to work, or have to constantly work on my car to get to work. 

[forester2002s]

'Headlights burning dim' could be related to a bad ground somewhere.

[Cougar]

If the fan trouble looks to be from the relay due to low voltage at the motor check the relay socket for heat damage due to a bad connection. The headlight trouble could be due to a bad connection to the power supply lead in the light socket. Check for signs of burning there also.

[Mugs]

OK, I had been waiting to see if I actually fixed the problem before I made a post of the results. I am confident that I got it figured out, and I thank you all for you help and support 

 

So lets start at the beginning. The day before all of this started happening the car just died at a stop light and would not start at all. Finally got it started and drove it home. So at this point I'm thinking possible main relay. I get in it to go to work the next day, and nothing, but crank, crank, crack. So obviously the stress level just escalated by ten fold. 

 

I get down under the dash, hoping that I can at least bang on the main relay and get it started to where I can get into work, and order a new one. Tap on it, nothing. Ok well let me swap whatever round relay is next to the fuel pump relay and see if that works. VROOOM, and were off like a bat out of hell, in case it dies again. 

 

Get to work, order a new FP and Main relay. Take out the existing fuel pump relay and lay it to the side. Takeout the un-known relay (that was originally the FP relay) and lay it to the side. Then pick up and re-install the original good relay. Then start my drive home, and the fan starts acting up as described in the previous post. 

 

So I start poking around doing some of the suggestion made, and after reading FairTax4me describing where the relay is, I think wait a minute. Lets start from the beginning, none of this started until, blah, blah, blah. Go out to the car, turn on the fan (it was working at that time) un-plug mystery relay and boom, flat line, no fan. So I must not have been paying attention when I replaced it with what I thought was the original, and ended up replacing it with the bad FP relay. I still had it, so I re-installed the true original one, and we have been groovy ever since 

 

As far as the lights, I diag'ed it to be loose tabs at the bulb connector. I took a small flat head screw driver and bent them smaller, so they would clamp more securely on the bulb, and were all good there as well. 

 

Thanks so much guys for helping me through this, and just being able to bounce ideas off of you all. Like I said, I hate, and am not good, with electrical, you want me to tear down an engine and put it back together, and have it start, no problem. You need me to figure out why your car stalls at 3500 rpm's while going up hill, and turning left...BIG PROBLEM   

 

So thanks again. 

 

Cheers

Mugs

Edited by Mugs, 03 September 2013 - 11:18 PM.

[Cougar]

Glad you got it fixed. Thanks for the update.

[ivans imports]

i bet fan is on its way out and pulling to many amps i would start looking for new one soon

[Mugs]

i bet fan is on its way out and pulling to many amps i would start looking for new one soon

Good advise. I don't think its the fan though. I think it was because I put in the bad fuel pump relay in, instead of the existing good fan really.