Fans/Electrical Question...
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From: Cheyenne, Wy
Fans/Electrical Question... I need to get my fans working again. They have proper power to the relays, fuse is good, relays are new, coolant temperature gauge/sensor is operational , PCM is programmed to turn on at 180/190 and when I give the fans direct power they turn on so I have come to the conclusion that there is a wiring problem somewhere between the relays and the fans because my SLP fan switch doesn't even turn the fans on.
With that being said I need a quick fix to get the fans working properly ASAP. What wire can I tap into that comes out of the fuse box and will make the fans operate properly?
I would prefer them to work like they normally would but if I can't do that then I am just going to say screw it and direct wire a switch to turn them on and off as needed. Anyone have any info that can help me in this matter? OR anything I might have missed?
With that being said I need a quick fix to get the fans working properly ASAP. What wire can I tap into that comes out of the fuse box and will make the fans operate properly?
I would prefer them to work like they normally would but if I can't do that then I am just going to say screw it and direct wire a switch to turn them on and off as needed. Anyone have any info that can help me in this matter? OR anything I might have missed?
If you are certain there's a problem somewhere between the relays and the fans, start tracing the wires...seems pretty obvious to me. A few minutes with a multimeter should reveal the problem.
But if you insist on taking the easy way out, (
), the fans draw a good bit of power so I would not recommend powering them directly off of the fuse box. You'd have to wire them into the (+) terminal and add a relay from the fuse box (I like the PCM/IGN fuse - that turns the fans on when the key is on). Or since you know the wiring between the fuse box and fans are bad, tie a new wire into the existing relay.
But if you insist on taking the easy way out, (
), the fans draw a good bit of power so I would not recommend powering them directly off of the fuse box. You'd have to wire them into the (+) terminal and add a relay from the fuse box (I like the PCM/IGN fuse - that turns the fans on when the key is on). Or since you know the wiring between the fuse box and fans are bad, tie a new wire into the existing relay. My fans don't turn on anymore and I've had many people tell me that it's the fans themselves cause if I put a fuse in it will blow it right away. Maybe similar issue maybe not. Something to look into.
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From: Cheyenne, Wy
I used a test light to diagnose the fuse box however I need to determine other areas but I am not able to touch the car again until Monday afternoon.
On the fuse box, the fan fuse receives a constant hot
Relay sockets receive a constant hot on the #1 sockets and are hot with key on on the #5 sockets.
How do I determine whether or not the relays are receiving the proper signal to engage at the correct time?
For the SLP fan switch, what exactly would I be looking for considering it is a plug n' play device?
Also I am uneducated on wiring systems so I am still learning so please understand and be patient, but according to this schematic http://shbox.com/1/fan_schematic_1995.jpg I know the ignition runs to the 10A fuse in the U/H Fuse Box...then to the relays which control each fan and the high/low settings. I also see 2 wires that I assume run from the PCM to the relays to tell the fans to turn on at tempurature, and 1 other wire that is labeled "Fuse Link" to B+......WTF is that and where does it go? To the junction box? Also I assume the ground from Relay #3 is the one mentioned that grounds under the ABS Block, but where does the ground coming off of the Right Side Fan ground at?
I know this is a lot of questions...a lot of which are basic and ridiculous, but I am trying to learn.
On the fuse box, the fan fuse receives a constant hot
Relay sockets receive a constant hot on the #1 sockets and are hot with key on on the #5 sockets.
How do I determine whether or not the relays are receiving the proper signal to engage at the correct time?
For the SLP fan switch, what exactly would I be looking for considering it is a plug n' play device?
Also I am uneducated on wiring systems so I am still learning so please understand and be patient, but according to this schematic http://shbox.com/1/fan_schematic_1995.jpg I know the ignition runs to the 10A fuse in the U/H Fuse Box...then to the relays which control each fan and the high/low settings. I also see 2 wires that I assume run from the PCM to the relays to tell the fans to turn on at tempurature, and 1 other wire that is labeled "Fuse Link" to B+......WTF is that and where does it go? To the junction box? Also I assume the ground from Relay #3 is the one mentioned that grounds under the ABS Block, but where does the ground coming off of the Right Side Fan ground at?
I know this is a lot of questions...a lot of which are basic and ridiculous, but I am trying to learn.
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From: Little Rock, AR
With relays removed, you should see a ground at D2 when you flip your fans switch to low. You should see grounds at D2, F5 and J2 when flipped to high. If you don't see that, then there is no continuity from the switch to the relays. You should see the same grounds when the PCM commands the fans on low or high.
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Joined: Dec 2008
Posts: 4,145
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From: Little Rock, AR
It might on low speed, since the fans are run in series in low speed. The RH fans should still run at high speed, even if the LH fan does not work.
