Overheating
Supporting Vendor
Joined: Apr 2012
Posts: 2,671
Likes: 369
From: Forney TX
I checked the high speed fan (dark blue wire with high speed enabled) at the PCM and was getting 1.5v. I tried grounding the right fans ground to a good ground source (battery) and still clicked. So now I'm off to checking all connections (relays and fans) with the voltmeter for high speed operation.
I have a service manual that has the wiring schematic.
Also, the post above yours was with the relay off for each test. This time it will be with them connected using a thin wire so the relay can be in place during test.
If I can't find the problem I'll just have it when the low speed turns on it's actually the high speed and just set the high speed temp operation to 284*. And how do you pull enough slack out of the fuse block to check the connections? I can get maybe 2" off the block and that's it.
I have a service manual that has the wiring schematic.
Also, the post above yours was with the relay off for each test. This time it will be with them connected using a thin wire so the relay can be in place during test.
If I can't find the problem I'll just have it when the low speed turns on it's actually the high speed and just set the high speed temp operation to 284*. And how do you pull enough slack out of the fuse block to check the connections? I can get maybe 2" off the block and that's it.
The PCM throws a ground, not a hot.
Use You don't even have to cut the control wires. You're going through a lot more trouble than you need to solve this problem. You can skin back the two relay control wires and run them to pin 85 on a good, Bosch, Potter Brumfield, Tyco or other non-Chinese, high current relay and run 12v to pin 86. Run 12v to 87 and your load (fans) to pin 30. Done. You'll still have 2 stages of fan control from your PCM.
Thread Starter
Drifting
Joined: Apr 2011
Posts: 1,801
Likes: 1
From: Tulsa Ok
You say to skin back the wires and I'll have 2 stages but won't the high speed relays keep clicking if I do this?
I'll try that once I eliminate my current issue. Do you know how to separate this?
I'll try that once I eliminate my current issue. Do you know how to separate this?
Last edited by danieloneil01; Sep 21, 2014 at 01:45 PM.
Supporting Vendor
Joined: Apr 2012
Posts: 2,671
Likes: 369
From: Forney TX
As for the block, it's held together by the 3 large metal pins, the ones that the top cover screws into. To get it apart, I heat up the pins with a micro torch, place the block face down on the vise with the jaws opened about 1.5" apart. Heat it up and use about 1 1/4" punch knock the pins out. To hold it back together, you can make a plate and run a screw through it into the pins to hold it together afterwards.
I'll upload pictures in a bit.
Thread Starter
Drifting
Joined: Apr 2011
Posts: 1,801
Likes: 1
From: Tulsa Ok
Before I separate the block to determine if that's the issue I'm going to solder wires to all 3 relays then set the spliced ends into the distribution block to see if the high speed fans come on. If not then I know the fuse block isn't my issue. Yes it seems like a lot of work but I got a low IQ count.
Is there no wires connecting some of the relays together?
Is there no wires connecting some of the relays together?
Supporting Vendor
Joined: Apr 2012
Posts: 2,671
Likes: 369
From: Forney TX
I don't recommend soldering leads to relays, but if one insists on doing so, that they be careful and quick about it because it's possible to negatively affect the factory soldering work at the other end of the leads. if you do decide to disassemble the block, you can slide off the loose terminals and flip them over and then solder that end to the block (again carefully and quickly with a nice, high powered iron). That will possibly provide you with an end with more tension. You can also increase tension on the leads by adding a dab of solder to the legs to bulk them up and then sand/grind them down to the desired thickness. 
I also recommend using separate relays to ensure they're not the problem.
I also recommend using separate relays to ensure they're not the problem.
Last edited by BLOWNBLUEZ06@RKT Performance; Sep 21, 2014 at 03:20 PM.
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Supporting Vendor
Joined: Apr 2012
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From: Forney TX
Thread Starter
Drifting
Joined: Apr 2011
Posts: 1,801
Likes: 1
From: Tulsa Ok
Well I hooked it all up using two HD relays for low and high even though the fans would run in high speed no matter what. I really didn't feel like getting the high speed wire from the pcm at the pcm so I got it from under the fuse block. When I went to enable high speed the relay clicked over and over not allowing the fans to run. I'm to the point of just not caring enough in the Houston heat in a garage to go further and try it off the PCM. From making 2 runs to the auto parts store I've been in the heat for 5hrs. I work on it more than I actually drive it and that has to end. Tomorrow I might get my condenser in and hopefully have AC soon, just in time for winter, lol.
So I programmed hptuners to nuke the high speed altogether.
I took it for a spin without the top cover and when the fans are on the temp stays at 187-190 with a 187 tstat. Outside temp is low 90s.
If you don't mind I can post the diagram I made and I'll include the PCM wire locations for the low and high speed under the fuse block if one is so inclined to go that far.
So I programmed hptuners to nuke the high speed altogether.
I took it for a spin without the top cover and when the fans are on the temp stays at 187-190 with a 187 tstat. Outside temp is low 90s.
If you don't mind I can post the diagram I made and I'll include the PCM wire locations for the low and high speed under the fuse block if one is so inclined to go that far.
Last edited by danieloneil01; Sep 22, 2014 at 07:01 PM.
Team Owner
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Well I hooked it all up using two HD relays for low and high even though the fans would run in high speed no matter what. I really didn't feel like getting the high speed wire from the pcm at the pcm so I got it from under the fuse block. When I went to enable high speed the relay clicked over and over not allowing the fans to run. I'm to the point of just not caring enough in the Houston heat in a garage to go further and try it off the PCM. From making 2 runs to the auto parts store I've been in the heat for 5hrs. I work on it more than I actually drive it and that has to end. Tomorrow I might get my condenser in and hopefully have AC soon, just in time for winter, lol.
So I programmed hptuners to nuke the high speed altogether.
I took it for a spin without the top cover and when the fans are on the temp stays at 187-190 with a 187 tstat. Outside temp is low 90s.
If you don't mind I can post the diagram I made and I'll include the PCM wire locations for the low and high speed under the fuse block if one is so inclined to go that far.
So I programmed hptuners to nuke the high speed altogether.
I took it for a spin without the top cover and when the fans are on the temp stays at 187-190 with a 187 tstat. Outside temp is low 90s.
If you don't mind I can post the diagram I made and I'll include the PCM wire locations for the low and high speed under the fuse block if one is so inclined to go that far.
Thanks,Matt
Thread Starter
Drifting
Joined: Apr 2011
Posts: 1,801
Likes: 1
From: Tulsa Ok
I went full retard and dumped my two 30 amp relays and got two 75 amp relays (Oreillys, 50 each) and separated each fan to run off each relay. I'll get a diagram up soon but it's only for low speed off the PCM but my fans will run in high speed no matter what, with or without the ac on. I have hptuners so I turned off all stage 2 runs.
Thread Starter
Drifting
Joined: Apr 2011
Posts: 1,801
Likes: 1
From: Tulsa Ok
No, fans must stay on for probably 90% of the time. I have them come on at 205 and off at 190. Car runs between 190-207 cruising on the highway. This is without a top cover though. I tried leaving the fans off on the highway early in the morning when it was 72* and the temp climbed to 230 before I let the car turn the fans on through hptuners. Hoping it is strictly because of the top cover missing.
When I get time after my move I'll see if I can find a big enough flat piece of aluminum and try to make a top cover with little gaps. I think it would help also to put some pieces on the sides of the radiator too.
When I get time after my move I'll see if I can find a big enough flat piece of aluminum and try to make a top cover with little gaps. I think it would help also to put some pieces on the sides of the radiator too.
Last edited by danieloneil01; Sep 27, 2014 at 05:43 PM.