Request for an experienced automotive electricians help please.

[SYKRAMMAN]

Im having an issue with my ac fan, I know what’s wrong but don’t know how to run power to it to turn on with ac. There isn’t any power from tipm. I have another tipm on order but need the ac now though. Any help is greatly appreciated.

 

[crash68]

For a temporary "fix", wire the cooling fan to run when the truck accessory/ignition is on. If it's hot out there won't be an issue with over cooling.
just and idea

 

[SYKRAMMAN]

Thought of that but don’t want to have it running constantly. It probably won’t hurt anything though, another tipm is coming next week so that should hold me over I guess. Thnx for replying though.

I may run a temporary switch. I would need an inline fuse, correct?

 

[justin13703]

If you want to go to the work of making it run with the ac, here’s what I would do. Keep in mind I’m at work so I can’t look up the exact wire colors you’ll need.

Get a 30 amp automotive relay. There should be two wires going to your ac clutch. One of them will get 12v when the compressor is on. Splice into this wire, and connect it to pin 85 of the relay. Ground pin 86.

Now for the power side of it, run a 12 gauge wire from your battery positive to pin 30 of the relay (fuse this as close to the battery as possible). Now run another 12 gauge wire from pin 87 of the relay to whichever wire is the 12v feed to your condenser fan (you may need a diagram to find this).

So in short, compressor 12v to pin 85, ground to pin 86, battery to pin 30, condenser fan to pin 87.

 

[SYKRAMMAN]

If you want to go to the work of making it run with the ac, here’s what I would do. Keep in mind I’m at work so I can’t look up the exact wire colors you’ll need.

Get a 30 amp automotive relay. There should be two wires going to your ac clutch. One of them will get 12v when the compressor is on. Splice into this wire, and connect it to pin 85 of the relay. Ground pin 86.

Now for the power side of it, run a 12 gauge wire from your battery positive to pin 30 of the relay (fuse this as close to the battery as possible). Now run another 12 gauge wire from pin 87 of the relay to whichever wire is the 12v feed to your condenser fan (you may need a diagram to find this).

So in short, compressor 12v to pin 85, ground to pin 86, battery to pin 30, condenser fan to pin 87.

Hey, excellent, that’s exactly what I was looking for. thank you very much for the instructions. I will do just that n let you know how it turns out.

 

[justin13703]

Hey, excellent, that’s exactly what I was looking for. thank you very much for the instructions. I will do just that n let you know how it turns out.

No problem. Let me know if you have any questions.

I forgot to mention, the wires going to pins 85 and 86 (the compressor signal wire and ground wire) don’t have to be very thick. 18 gauge or something like that is fine. All they are is a trigger to trip the relay. The relay itself pulls very little amperage. Miliamps actually. The only heavier wires you have to use are the battery and fan connections from pins 30 and 87.

 

[SYKRAMMAN]

No problem. Let me know if you have any questions.

I forgot to mention, the wires going to pins 85 and 86 (the compressor signal wire and ground wire) don’t have to be very thick. 18 gauge or something like that is fine. All they are is a trigger to trip the relay. The relay itself pulls very little amperage. Miliamps actually. The only heavier wires you have to use are the battery and fan connections from pins 30 and 87.

Ok, sounds good. Thanx again man.

 

[justin13703]

Ok, sounds good. Thanx again man.

No problem

 

[McBroom]

If you want to go to the work of making it run with the ac, here’s what I would do. Keep in mind I’m at work so I can’t look up the exact wire colors you’ll need.

Get a 30 amp automotive relay. There should be two wires going to your ac clutch. One of them will get 12v when the compressor is on. Splice into this wire, and connect it to pin 85 of the relay. Ground pin 86.

Now for the power side of it, run a 12 gauge wire from your battery positive to pin 30 of the relay (fuse this as close to the battery as possible). Now run another 12 gauge wire from pin 87 of the relay to whichever wire is the 12v feed to your condenser fan (you may need a diagram to find this).

So in short, compressor 12v to pin 85, ground to pin 86, battery to pin 30, condenser fan to pin 87.

Hey, excellent, that’s exactly what I was looking for. thank you very much for the instructions. I will do just that n let you know how it turns out.

That's an awesome write up. I've had aftermarket relays and could never remember how to wire them up. Plus I need to remember this for the light bar I'm wanting to get.

I Love my 18 Ram 2500 4x4 CC U.S.M.C.(ret) CPL

 

[SYKRAMMAN]

That's an awesome write up. I've had aftermarket relays and could never remember how to wire them up. Plus I need to remember this for the light bar I'm wanting to get.

I Love my 18 Ram 2500 4x4 CC U.S.M.C.(ret) CPL

Hey hey hey, no stealing, mine mine mine! Jk, all yours.

 

[McBroom]

Hey hey hey, no stealing, mine mine mine! Jk, all yours.

I'd never think of highjacking your thread just an added thought. I loved the way the relay pins were layed out/described.
That's all. Lol [emoji4]

I Love my 18 Ram 2500 4x4 CC U.S.M.C.(ret) CPL

 

[JB1]

Im having an issue with my ac fan, I know what’s wrong but don’t know how to run power to it to turn on with ac. There isn’t any power from tipm. I have another tipm on order but need the ac now though. Any help is greatly appreciated.

I read on a dodge ram FB page the other day, an owner had a similar problem as yours and the ignition switch was causing it. He replaced that and it fixed his AC. It sends some signal to the fan motor

 

[SYKRAMMAN]

I read on a dodge ram FB page the other day, an owner had a similar problem as yours and the ignition switch was causing it. He replaced that and it fixed his AC. It sends some signal to the fan motor

Its gotta be the tipm cause I just swapped it for another because the one I had, the asd relay wasn’t grounding out, now this tipm, the ac fan relay isn’t grounding out, it was an immediate cel as soon as I put this one in. No power from fan plug, and no power from tipm fuse. It was working before I swapped them. Same issue, just a different relay this time. So automotive/lkq is shipping another free of charge. This will be the fifth one I’m trying, every other one has had an issue.

 

[JB1]

Wish I could find that post on Facebook “Dodge Ram page”, he was chasing relays too but found the ignition switch was shorting something out, seems there’s a few connections that go to the fan, maybe for accessory I dunno. Just something to consider

 

[SYKRAMMAN]

Wish I could find that post on Facebook “Dodge Ram page”, he was chasing relays too but found the ignition switch was shorting something out, seems there’s a few connections that go to the fan, maybe for accessory I dunno. Just something to consider

Hmmm, maybe that’s causing the tipm’s to go bad from the gate?

 

[SYKRAMMAN]

I’ll try this last one, and if it has the same issue, I’ll try the switch. Truck actually came with a brand new switch because they thought the other was bad but turned out not to be so he never installed or returned it. Yay for me.

 

[JB1]

Well I can’t guarantee it, but this guy was so happy it fixed his truck he was telling everyone lol. I found it odd too.

I’ll search again for that post

 

[justin13703]

I remember a while back reading a thread about an ignition switch causing issues with the hvac fan. But I thought it was the interior blower that stopped, not the condenser fan like in this case. I couldn’t believe for a second that the ignition would cause issues with the blower fan, but apparently it did. This is the outside fan, but I guess anything is possible lol. Actually I don’t think the problem was in the ignition switch itself, but a little module that attaches to it.

Did you end up putting that relay in?

 

[justin13703]

That's an awesome write up. I've had aftermarket relays and could never remember how to wire them up. Plus I need to remember this for the light bar I'm wanting to get.

I Love my 18 Ram 2500 4x4 CC U.S.M.C.(ret) CPL

Thanks, most automotive style relays have 5 pins. 85, 86, 87, 87a, and 30. 85 and 86 are the coil pins. When you have ground to one, and 12v to the other, the relay activates, which then physically connect pins 30 and 87 together. This is what turns the load on. So generally 30 is your main power connection that will power the load, and 87 is the output to the load. When either 12v or ground is removed from pins 85 or 86, the relay turns off, disconnects pins 30 and 87 from each other, and the load turns back off.

Pin 87a isn’t used quite as much. It is a NC contact (normally closed) which means that when the relay is off, pins 30 and 87a are connected. When the relay turns on, pins 30 and 87a disconnect, and 30 and 87 connect. The technical names for all the pins are: 85 and 86 are the coil, 87 is NO (normally open), 87a is NC (normally closed), and 30 is Common (because depending on the state of the relay, this one is always either connected to pin 87 or 87a).

Didn’t mean to get off track here lol. Relays are really simple, if you have any electrical knowledge you can sit and mess with one with a multimeter and see what’s going on. Just think of them as little automatic light switches, that turn themselves on or off when they get a signal.

 

[SYKRAMMAN]

I remember a while back reading a thread about an ignition switch causing issues with the hvac fan. But I thought it was the interior blower that stopped, not the condenser fan like in this case. I couldn’t believe for a second that the ignition would cause issues with the blower fan, but apparently it did. This is the outside fan, but I guess anything is possible lol. Actually I don’t think the problem was in the ignition switch itself, but a little module that attaches to it.

Did you end up putting that relay in?

I’m going to work on it tomorrow and see if I can screw something up lol, I’m terrible at electrical **** on vehicles. I’ll update.