It’s been really cold lately so I decided I’d finally try and troubleshoot why my blower doesn’t run.
My headunit was stolen awhile ago, all the wiring was exposed and my blower was working until the wires touched, sparked and lost power to accesories. Replaced the fuse and the new headunit/dome lights worked but the climate controls would not on any speed.
Took the glovebox out today and the resistor had one set of broken coils between L0 and M1, so the first and second speeds? After reading about heater related issues it seems that the resistor wouldnt be the culprit as it should still work on the highest setting (which it doesn’t). I was reading that when it doesn’t blow on any setting, to check the switch, I’m not sure what switch is in question though? Ignition?
Checked the 40A (I believe) Blower Motor fuse also, it was awhile ago and to the best of my recollection, it was good otherwise I would’ve replaced it… I’d check again right now if it wasn’t pitch black and snowing lol.
The whole thing seems to coincidental to be anything other than a fuse/resistor to me? Surge of electricity from the exposed wiring = fried fuse+resistor+switch?
To troubleshoot the system you really need a multimeter, some tests can be done with a test light.
The first thing to test for is power, [12V+] on the blue/white at the 2pin connector on the blower motor, [blower motor power] it should be hot when ign. switch is in the run position.
If there is power on the blue/white lead then test for a ground on the blue/black lead with blower speed switch set to 4, [high speed].
If you have both power and ground replace the blower motor.
If there is no power, check for power on the blue/white lead at the ign. switch harness.
If there is no ground, use a jumper lead, [scrap piece of wire] to supply a ground directly to the blue/black lead at the 2pin blower motor plug, if blower works you will need to pull the “Heater Control Panel” and test for a ground on the black lead at “HCP” plug(s). there are 2 black leads, both need to show a ground.
If grounds are good test for ground on the blue, [speed 1] blue/white, [speed 2] blue/yellow, [speed 3] and blue/black, [speed 4], the speed switch must be in the appropriate position to test the leads.
If the two black leads have a ground but no ground output on the 4 speed leads, you will need to replace the “Blower Fan Switch”.
Thats exactly what he’s talking about. Best of luck in resolving this. I’ve had the same issue myself and it happended in the winter. Fortunatly it was just my blower motor that got burned out. He’s correct in getting that multimeter it will be your best friend through this process.
“Thats exactly what he’s talking about.” No it’s not.
The one that plugs into the back of the resistor pack is a 4pin plug.
The blower motor plug is a 2pin plug and is plugged into the blower motor itself, access from under dash pass side,[right above where a passengers feet would be].
The resistor pack is mounted into the blower box from up above, behind glove box.:tapfing:94
Had this issue when I bought my car, kid supplied me with a new motor, installed it but still didn’t work.
Rand a new power wire with an inline fuse and BAM!!! got blower!!!
Good luck, If you need the electrical troubleshooting pages out of the manual let me know. I’ve scanned them in for another thread and will find the others and post them up for ya here.
My blower motor stopped working the other day so i took out the resistor pack and one of the coils are shot. Then i jumped the blue and black with the blue and yellow wires and the blower cut on, but when i turn it off and on again it won’t cut on unless i mess with the switch and turn it off and on a couple of times. Do you think that if i get a new resistor pack and control switch it will solve my problem? Sorry about the running paragraph i took a pain pill for my back and i’m a little loopy right now
So it ended up being the blower motor that is bad, I replaced it, it worked for a couple hours and it ended up just turning off while I was driving (for no apparent reason), I yanked everything out again, fuses (main acc and blower motor) are good. Resistor is good, blower motor works, tested it independently on battery. Borrowing a multimeter again, can’t test for power in until tomorrow but it seems like it would either be the power in/ground to/from the blower motor itself?
Head unit also hasn’t worked since I started trying to fix blower lol, related?
Any suggestions are welcome, thanks.
Edit: I have a piece of wire running from the 40A blower motor fuse to the middle (always hot) free pin for the stereo to always have power so you can listen to it while the car is off (done by previous owner); not sure if it helps but trying to add as much info as possible=\
LOL, remove the wire running from the 40A fuse to the free pin, there are better ways to have the stereo work without key on then powering up a switched 40A circuit with a 20A constant power circuit.
Previous owner needs a kick in the nuts, it’s no wonder you have problems:roll:
Pull the 40A fuse and test it with the meter, or test both ends for power when ign. switch is on, [and after removing the jumper wire].
If fuse is good test for power at the blower motor plug on the blue/white lead, [ign. switch on] if you have power on the blue/white, check for ground on the blue/black lead with the ign. on and the blower switch on full, [#4].
Okay, took off the wire coming from the 40A fuse and the fuse was in good condition.
Tested for power coming in off the blu/wht and it had 12V when grounded on a seperate bolt on the chassis but the ground on the 2p connector was not working so I ran a seperate ground for testing purposes which did work correctly.
Tested it, had power and ground from the car side (2p connector power/independantly run ground) and the blower motor was working but it wasn’t turning on. Tested the amperage coming from the car (which was 12V) but it only gave 0.004A where as just a 1.5V battery gave 5A.
Tested for power coming in off the blu/wht and it had 12V when grounded on a seperate bolt on the chassis
, What was grounded to “separate bolt on chassis”???
This is really confusing…
Tested it, had power and ground from the car side (2p connector power/independantly run ground) and the blower motor was working but it wasn’t turning on.
I get the part about the “independently run ground”, [stock ground in 2pin connector was not working] but “blower motor was working but it wasn’t turning on”???:dunno:
Assuming you mean the blower motor works when you supply it a ground from an independent source but not when you use the switch, then the problem is either the blower motor resistor pack, [mounted into blower box above the blower motor, access from behind glove box] or the blower motor switch or wiring.
Unplug the 4pin plug at resistor pack and test the leads, all 4 leads should test as grounds, blue when switch is in the #1 position, blue/white #2, blue/yellow #3 and blue/black #4, if these leads do not test as grounds the blower switch is the problem, you will need to pull the switch and test for ground on the black lead going to it, [ground input] if it is a ground replace the switch.
You can also test the resistor pack by supplying an “independent ground” to each terminal one at a time, 4pin plug must be plugged in.94
The supplied ground from the 2p connector blu/blk wasn’t grounding… so I ran another ground for the sake of testing it.
The blower motor was working from another power/ground source (hooked it up to a small battery lol) but would not turn on when connected to the car.
I’m going to test the resistor pack, testing the power to the blu/wht on the 2p and using each invidiual lead as a ground? And if all of the leads test as a ground and the switch is bad, it is located right behind the speed selection knob correct?
Sorry for all the questions, wiring noob=[
Thank you very much though for the replies
OIC you used a completely diff. power supply to test the blower motor.
So try this, with the 2pin plugged into the blower motor, turn on the ign. and using a jumper wire, stick one end into the 2pin plugs ground, [blue/black] and ground the other end to any ground point, if blower motor works, do the same thing at the 4pin resistor pack plug, [also must be plugged in] one by one ground the 4 pins if you get 4 speeds the resistor pack is good, then you will need to move the the blower switch itself and do the tests I suggested before.
Sorry, not sure if blower switch can be replaced as a separate item or if it is part of HVAC control head, but the wiring you need to test is behind, [plugged into] the control head, you will only need to pull it if you do not get grounds on the 4 leads at the blower resistor pack.:whisper:94
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