AC/Heater not working
 

Hey so i got an 89 dakota 3.9l. Its the pretty basic model. No cruise control, no tilt steering, no power windows. So recently i was getting my ignition switch replaced and the "mechanic" who was working on it messed up a whole bunch of stuff. Besides not starting in park anymore due to the linkage or something needing adjusting... The main issue i noticed was the heater and ac didnt work after he was done either. Granted i didnt check it for a few days after so i guess it could be coincidence that it went out right after he was working on my ignition switch. So i had him come back and check it and he said there was no power to the ac fuse i believe. He said he thought it was a bad ac clutch relay and he showed me which relay he thought it was. I removed said relay and the truck wouldnt start so i assume that was the wrong relay. Just trying to figure out which relay is which so i can try swapping it out and then going from there if that doesnt work. I already replaced the blower motor resistor. Im just thinking maybe either something in the dash got unplugged while he was working on the ignition if not the relay just going out. Just need some guidance on any checks i can run to diagnose this problem. I have a multimeter and a little bit of mechanical incline but im not a mechanic so please try not to be too vague, it will be much appreciated. Attached is a picture of the only four relays i see under the hood.https://cimg3.ibsrv.net/gimg/dodgefo...8b45f47999.jpg

And when i say the heater and ac arent working i mean there isnt any air moving on any setting. When i turn the ac on i dont hear the compressor click on or anything and the clutch isnt moving. If there is any more info that would help you guys assist me please let me know. I really need to get this issue fixed fast. I dont mind the lack of ac so much but id really like to get it up and running for my nieces, they wont stop saying how hot it is when we're driving and i feel guilty.

So basically, you are saying the fan is not blowing? Have you checked all the fuses?

Yes the fan is not working. I checked all the fuses, neither of the two ac/heater related fuses were blown. The guy who checked it said that there wasnt any power coming into the 30a ac fuse.

The relay you unplugged, was it the one on the left? I think that is the starter relay
I have a 87 service manual and on the 87, that is a starter relay. I dont have the other two.
But if the other two are the same style relay, you could swap them and see if that is it.
But FWIW, I dont believe the 87 has a heater motor relay.
He may be sending you on a wild goose chase!!

According to the number stamped on the middle relay, (5233205) that is a fuel pump relay.

The middle one was the original one he told me he thought it was and that was the one i unplugged and it wouldnt start. I went and grabbed some relays from the junk yard and tried changing each of the four relays and still nothing. I did discover that there is a short in the circuit which goes to the 5amp fuse which is for the glove box, key in ignition lamps, radio and clock memory, and a few others. Not sure where exactly the short is yet or if that could have anything to do with it even tho that fuse isnt labeled with anything relating to the ac or heater.

Could there possibly be a fusable link in between the battery and fuse box that couldve blown maybe? If there is no relay then there has to be either another fuse or a break in the wiring from the battery to the fuse box correct?

"Messing with ignition switch" ... I'll bet that either the switch isn't fully plugged into the harness, or it's messed up also.

Presuming it's like my 1988, here's an attached PDF of the ignition switch. Check and see if you have backup lights; if you do, then it's most likely the lead inside the fuse block. If you don't, check that wire back to the ignition switch and verify that it's turning that line on ...

RwP

Ok so you might be onto something because my reverse lights are not working. So according to that ignition diagram im looking for the black and red wire that is part of the ignition harness? And just tracing that wire to make sure its all plugged in properly and that nothing is obviously wrong with it correct? Thanks in advance for your response. And thanks everyone else who responded i appreciate any help i can get.

I'll add that you probably want to pick up the factory service manual from Ebay, RockAuto, or direct from Bishko to get those wiring diagrams and schematics; along with the rest of the service manual.

If it's all plugged in, you may just have a bad ignition switch. They're not too bad pricewise, but tilt and non-tilt get different switches. Here's a few part numbers at RockAuto: https://www.rockauto.com/en/catalog/...er+switch,4700 .

RwP

Well its a brand new ignition switch so i hope thats not it

ok so i checked the ignition switch to make sure it was plugged in all the way and it was. i didnt see anything obviously wrong with the wires that ran to the fuse box. so i decided to double check and just make sure there wasnt any power to the fuse as i hadnt actually checked it myself, just took the guys word for it. so i tested it and it wasnt getting power to the #4 fuse which is the 30amp for a/c & heater blower motor. i decided to check the rest of the fuses and there were two other fuses that werent getting power as well. the #2 fuse which is a 20amp for a/c cycling clutch switch and backup lamp feed and also the #12 fuse which is the 4amp fuse for the cluster illumination, radio a/c & heater control, ash reciever, overdrive indicating & cigar lighter lamps.

also i do have some wiring diagrams but they are for the models with the pdc. i have yet to find one with my exact model shown so ive been hesitant to fork over any money for a digital version since im assuming it will be the same one i have already. a lot of stuff is very similar obviously its just all different on this wiring stuff without having the pdc and all those relays and fuses under the hood.

Ahem.

IF you pick up the official Factory Service Manual, it'll have the right wiring diagrams. Diagrams with a PDC aren't for a 1989.

Don't keep grabbing "something close" or you'll keep getting McDonald's when you wanted a ribeye steak ...

As I type this, the Bishko FSM on DVD is only $22.79 at RockAuto. EBay will also have the old paper copies off and on; prices vary wildly there.

RwP

Ok ill get one of those. So would you still lean towards a faulty ignition switch with all three of those fuses not getting power?

Quote:

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Originally Posted by Unclebuck916 (Post 3389913)

Ok ill get one of those. So would you still lean towards a faulty ignition switch with all three of those fuses not getting power?

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Just guessing on my behalf. But if it was working before they replaced it, then I would put a bet on it!!
And sorry I had to pull out yesterday and go on a service call. Left early this morning and just got in.

ok thanks ragtop. im leaning towards that as well now considering the fact that replacing the ignition switch didnt even solve the initial problem that it was suppose to. the guy who worked on it diagnosed my original problem which was every now and then when i started my truck the abs and emergency brake dash lights stayed on and the radio and dome lights had no power. he diagnosed that to a bad ignition switch, replaced the ignition switch with a bwd one from oreilly and thats when the problem with the ac/heater popped up as well as my truck not starting in park now. he actually came back one time and adjusted the linkage i believe he said, got my truck starting in park but then after driving it and turning it off it wouldnt start in park again. so im thinking im just going to slap the old ignition switch back in and find a different mechanic who can adjust the linkage properly.

I don't think the ignition switch has anything to do with the dome lights...

It doesn't, at least on none of the schematics I have (88,95,96).

I doubt 89 is radically different from my 1988 for that matter.

RwP

I must have a short in the interior lights circuit or something as well because that fuse just popped when i turned on my dome light. Im guessing that is a completely seperate issue from the ac/heater issue. Im gonna swap out that ignition switch tomorrow and ill let you guys know if that solves the problem. Thanks again for all the input. Much appreciated.

I'm not an electrical guy but I read the thread and I thought that maybe there was a short caused while changing the switch without disconnecting the battery and now something is burned out. ??? IDK if that is even possible as I have never changed the ignition switch.

so i swapped out the ignition switch and put the old one back in and still no power to those three fuses. i have checked multiple times in the dash to see if i see any wires unplugged or anything and i just dont see anything obviously out of place. there are a few female connectors that dont appear to have anything that plugs into them but i remember seeing those like that before ever having any work done on it. any ideas on what to try next? thanks in advance.

Pull the fuses and check the feed side, see if there's 12V there at all.

Follow the wiring back to the ignition switch, see where 12V disappears.

Make sure there's 12V out of the ignition switch when it's turned ON.

Past that, you may need an old priest, a young priest, and a chicken ...

RwP

***UPDATE W/ FIX***

So after i had decided i spent enough time trying to figure it out i took it into the shop and I will explain the problem and the fix as best as i could as there was a slight language barrier. but what i got from what he said was that someone had previously bypassed some relay or fusible link maybe (couldnt understand what he was saying on this part im just assuming he meant relay or fuse) probably when it went bad and instead of replacing it they just connected the wires without it. and apparently they didnt do a good enough job as thats where the short was. they had tucked the wires back into the harness with the rest after taping them up so i couldnt tell that anyone had done anything. so the fix was either for me to go and get him a wiring diagram so he could make sure he ran it as it came factory with the proper relay/fuse. the other option he gave me was to run a hot wire to my blower motor(?) with the only downside being i just have to make sure i turn it off when i turn the car off obviously but its kinda hard not to, its rather loud. i went with the second option as he only charged me $30 for the repair on top of the original $60 for the electrical diagnosis which i had already agreed to. and for another $30 he adjusted my linkage so my car starts in park again. so finally after a month or so my truck is back to almost exactly how it was before this whole craigslist from hell mechanic ordeal began. i wanted to thank everyone who helped lead me in the right direction. i told him everything i had gathered from you guys and he said it definitely sped up his diagnosis as i had it narrowed down pretty well for him.

It is always satisfying to help but more so when we find out the results of the efforts. Thanks.