Solved My blower motor won't turn on.

[LoquetusofBorg]

You might look for evidence of heat damage in the blower motor relay socket and connector lugs. swap in different relay ( just swap it for another one like it) and see if this makes a difference.

I will do that as I still have the old resister. I should show you a pic of the old resister not only how rusty it is but the mice has some insulation stuck in there to and it still worked and never caught fire in 4 years of driving.

 

[Turdle]

Not the resistor, the relay. In the power distribution box. ( the box near the air cleaner you mentioned has relays for rear washer pump and lights)

Look here


http://www.explorerforum.com/forums/showthread.php?t=180814

 

[LoquetusofBorg]

Not the resistor, the relay. In the power distribution box. ( the box near the air cleaner you mentioned has relays for rear washer pump and lights)

Look here


http://www.explorerforum.com/forums/showthread.php?t=180814

I checked the fuses in that box and they were all good, this one your showing is actually up on the drivers side right next to the battery. I have no idea how to check a relay for continuity. The box I was referring to is right next to the bottom of the air filter box, between the radiator and the air box, I have no idea what that box filled with relays is for nor is it in my manual, but I learned of it's existence here in this forum. I took out every relay in it, cleaned and sanded every post on them, then took a q-tip with alcohol and cleaned the sockets best I could. Would you happen to know what those are for? Thank you for responding. I am going to spend the rest of the night reviewing the eatc service manual I found online. This manual I have not seen in this group and if you would like a copy I will post it to any group you would link me to. Thank you for all your help and I hope you can think of an easy fix before I start to rip it apart.
Sincerely,
Robert

 

[J_C]

I will do that as I still have the old resister. I should show you a pic of the old resister not only how rusty it is but the mice has some insulation stuck in there to and it still worked and never caught fire in 4 years of driving.

I'm not sure if I am misunderstanding you, or if some people are using the wrong terminology.

EATC is automatic climate control. It does not have a resistor module, though some people, even sellers erroneously call its module a resistor module when it is instead a transistor module. The two are not interchangeable.

If you have the automatic climate control head unit in the dash, you need the transistor module for it, not the resistor module.

This is the transistor type needed for EATC:

This is the resistor type you cannot use with EATC, is only for manual controls:

 

[BrooklynBay]

You could use a jumper wire in the relay socket to see if the blower motor turns on.

 

[LoquetusofBorg]

I'm not sure if I am misunderstanding you, or if some people are using the wrong terminology.

EATC is automatic climate control. It does not have a resistor module, though some people, even sellers erroneously call its module a resistor module when it is instead a transistor module. The two are not interchangeable.

If you have the automatic climate control head unit in the dash, you need the transistor module for it, not the resistor module.

This is the transistor type needed for EATC:

This is the resistor type you cannot use with EATC, is only for manual controls:

Yes, you are correct. We are talking about hooking the eatc up to the resister one. It has been done before in this group and I believed he said it blew medium and hi but had no low, I find this acceptable. (I do have the transistor one but no wiring for it). But getting the blower to come on is what my problem is, with the diagnostic code "041" from the eatc I find it hard to believe that the ambient air temp sensor could shut the blower down so I think my problem is something else. Don't get me wrong, I am replacing that sensor, have ordered it and should be here in a couple of days. I am going to test the fan and resister today. Thank you for your help. Please keep the ideas coming as every idea helps.
Sincerely,
Robert

 

[LoquetusofBorg]

You could use a jumper wire in the relay socket to see if the blower motor turns on.

I will do that, thank you. Do you know how to test a relay? other then your jumper idea I don't know.

 

[LoquetusofBorg]

Not the resistor, the relay. In the power distribution box. ( the box near the air cleaner you mentioned has relays for rear washer pump and lights)

Look here


http://www.explorerforum.com/forums/showthread.php?t=180814

Turdle, have you found out or do you know what that little box of relays is for between the radiator and the bottom of the air box?

 

[LoquetusofBorg]

Going outside now to start the testing. Thank you to everyone for your suggestions they will be used today.
Robert

 

[BrooklynBay]

Testing a relay is simple since the relay is a simple device. Thin wiring in the socket is usually for the coil which has 2 wires. The main wires are thicker since they supply more current. There should be 2 wires for that. Those are the wires which you want to jump with a test wire to test the blower motor. Use a test light, and refer to the schematic diagram before using the jumper wire so that you plug it into the correct slot in the socket. You could also compare the wiring to the relay. Use the Ohm setting on a multimeter to test the resistance of the coil.

 

[LoquetusofBorg]

Testing a relay is simple since the relay is a simple device. Thin wiring in the socket is usually for the coil which has 2 wires. The main wires are thicker since they supply more current. There should be 2 wires for that. Those are the wires which you want to jump with a test wire to test the blower motor. Use a test light, and refer to the schematic diagram before using the jumper wire so that you plug it into the correct slot in the socket. You could also compare the wiring to the relay. Use the Ohm setting on a multimeter to test the resistance of the coil.

Well guys I have taken everything apart cleaned, tested with a multimeter and no such luck. The fan works as it should and after I took the relay out I gave it just a simple test putting power to 2 of the leads and hearing it click although I know that could be not good for the other 2 posts and they may not be doing there job. I have also taken the resistor plug and pulled the wires from there plastic surrounding. I filed them, They were not bad at all, and replaced. I will wait for the ambient air temp to get here but I honestly don't think that will help as it is working for the overhead console outside temp reading. Although I love how the digital system looks and is by far a superior system I think I may get my old wiring harness out cut the wires for the 3 knob system and patch it in as it is by far the more reliable system and hope that it works. I had no problems with the heating or air conditioning with the old system, although as I stated yesterday after the test drive that little rear blower cooked us out of there and when I adjusted the heat it worked flawlessly. I am truly tired of messing with something that should have been so simple but has anything but. I will wait for that sensor to come in and in the mean time start to figure out which way to go with the fan situation. I have not heard back from the 2 gents in the forum here that did this successfully with just the resister in place of the control module. I will check the wire schematics and see if it is possible to put the 3 knob system in this limited harness. I will let you know as time goes on guys. Thank you all!
Sincerely,
Robert

 

[BrooklynBay]

I don't know how much more you want to mess with this but there's another option. Get a home style digital HVAC thermostat with a fan-heat-central A/C automatic setting, and add your own 12 volt external relays. They make a line powered version which doesn't require small built in batteries, but is made to use an external transformer power supply. You set the temperature, and it will automatically switch between heat & A/C plus control the fan. There's also an input for a remote temperature sensor.

 

[LoquetusofBorg]

Problem Found. The 98 limited wire harness on the dash side does not have the same pin out locations on the fire wall to meet up with the 98 sport harness on the engine side. After I had tested everything under the hood there was simply no signal or power to any blower motor, ac relays or anything heat or cold. I took out my dash sport harness and compared it to the 99 limited dash harness I have laying around and Man I tell ya, everything else was the same, lights, engine management, transmission literally everything but the heat and air. SOAB!
I will ask on the proper venue for any one whom might have a 98 limited engine bay harness they would like to sell or trade for. To all those who chimed in, much thanks.
Sincerely,
Robert

 

[BrooklynBay]

Thanks for the update. Your thread is marked solved.