radiator fan on start up?

[chasingomas]

Probe the black wire on the harness to any ground, listen for the beep.

with the voltometer?

 

[07GtS197]

When you turn the ac on, the fan still doesn’t come on? As others have said, your best bet is to datalog to see if the ecu is calling for the fan to turn on and what temp the temp sensor is telling the ecu.

 

[chasingomas]

When you turn the ac on, the fan still doesn’t come on? As others have said, your best bet is to datalog to see if the ecu is calling for the fan to turn on and what temp the temp sensor is telling the ecu.

sadly no, I'm really lost at this point. How do I do that?

 

[cobrajeff96]

Search Youtube for a vid on how to put the multimeter into diode checking function.

 

[07GtS197]

sadly no, I'm really lost at this point. How do I do that?

You’ll either need an expensive scan tool or elm327 dongle and download Forscan. Once you have that we can walk you through what to do next.

 

[chasingomas]

You’ll either need an expensive scan tool or elm327 dongle and download Forscan. Once you have that we can walk you through what to do next.

for sure. Going to buy a new multimeter (shake my head), test everything. Go from there. I have a mac so I think I'll have to buy a cheapo laptop to run forscan but I can do that. i'll feel like a civic tuner in fast and the furious. I'll update when the testing is done.

 

[chasingomas]

okay, gonna post what I got, how I got there; feel free to help me if I did it wrong. Attached is where my wires were, and the setting was the dcv; 1 to the right of off. I put the black on bare metal, red touching stuff. I unplugged the harness to the rad fan so I could test that. I already felt dumb because the numbers jumped around a lot. Electricity from the ccrm to the fan was consistently much lower than the signal from the hood relays and the in cabin relays. I feel like that means its probably getting stuck somewhere along the line there? Please educate me, I tried to set it up like the videos I watched. thank you.

 

[cobrajeff96]

I recommend just doing a simple continuity test on the ground pin of the fan harness connector, whichever of them is colored black. You want the dial to the setting at 3 o'clock, the wifi looking symbol. One lead on the black pin of the fan connector (body harness side, not the fan itself) and the other lead on clean bare metal or any visible ground connection point such as the ones screwed into the upper radiator core support right behind the headlamps. The thing should beep if there is no break in that wire. Keep in mind that if you ever use this function for any reason, the test must always be done on an unpowered or de-energized circuit, as the multimeter sends out an electric charge of its own down one lead and expects to see it return on the other, hence the beep indicating continuity. Here, you're only doing it on a ground connection so it's generally safe regardless of the situation. If you ever put it on a normally-powered circuit (one which is fused), you must remove power from it or the entire car altogether, whichever is safer. If you don't follow this rule, you blow up the multimeter in some cases depending on how well it's designed and protected. The same goes for the ohm meter function which is one position above this diode checker function, the Omega symbol.

 

[SnakeBit!]

sounds like you ran direct power to the plug on the fan itself. did you also ground that plug when the fan ran?

have you, with the a/c on and car running, checked the plug that goes into the fan for power?

also, I am trying to remember if that car would also have a fusible link that is in the same circuit.

 

[SnakeBit!]

by the way, it may say elsewhere in this thread, i know we are working on a 96-04 possibly new edge, but this is a mustang, correct?

 

[chasingomas]

I recommend just doing a simple continuity test on the ground pin of the fan harness connector, whichever of them is colored black. You want the dial to the setting at 3 o'clock, the wifi looking symbol. One lead on the black pin of the fan connector (body harness side, not the fan itself) and the other lead on clean bare metal or any visible ground connection point such as the ones screwed into the upper radiator core support right behind the headlamps. The thing should beep if there is no break in that wire. Keep in mind that if you ever use this function for any reason, the test must always be done on an unpowered or de-energized circuit, as the multimeter sends out an electric charge of its own down one lead and expects to see it return on the other, hence the beep indicating continuity. Here, you're only doing it on a ground connection so it's generally safe regardless of the situation. If you ever put it on a normally-powered circuit (one which is fused), you must remove power from it or the entire car altogether, whichever is safer. If you don't follow this rule, you blow up the multimeter in some cases depending on how well it's designed and protected. The same goes for the ohm meter function which is one position above this diode checker function, the Omega symbol.

i was so nervous. Thank you so much. I felt each video said to do a different thing. Your explanation was great.

I brought to my friends uncles shop and it started working. He forced the fan on and it turned on at opperating temp and when we refilled the a/c. He thinks the fan wouldn't turn on with a/c because the freon wasn't in the system. He thinks I was too scared to let the car get warm once I installed the CCRM, which then let the fan turn on. I feel dumb and capable at the same time.

 

[chasingomas]

by the way, it may say elsewhere in this thread, i know we are working on a 96-04 possibly new edge, but this is a mustang, correct?

yes!

 

[chasingomas]

everything is happy. even the new pig tails. he even smiled and dapped me up about that. I learned 5 new ways to diagnose the cooling in a mustang. exhausted but proud. Thanks to everyone in the thread, even if you posted once.

Next I need to explore electric cause holy shit I was lost.

 

[ttocs]

electrical scares most enthusiasts and honestly it probably should. There is some book knowledge that is helpful when you get into it and the of course knowing how to use a meter is a good portion of it as well.

 

[SnakeBit!]

Glad it's sorted out...that's all that counts and you got a bunch of experience along the way!!!!

 

[chasingomas]

electrical scares most enthusiasts and honestly it probably should. There is some book knowledge that is helpful when you get into it and the of course knowing how to use a meter is a good portion of it as well.

where would I start bookwise? Tired of being scared lol

 

[chasingomas]

Glad it's sorted out...that's all that counts and you got a bunch of experience along the way!!!!

learned 4 new ways to diagnose cooling issues! and it's over haha