2014 RAM CV / Dodge Caravan P0480 Low speed rad fan inop.

 
Hi everyone, I have a 2014 Ram C/V in the shop with a P0480 for the radiator fan low speed not working. I have good 12V power at pins 30 and 85 at the relay, and if I jump power to pin 87, the fan runs as intended with low speed. However, when I use my scanner (Topdon Phoenix Max) to command the low-speed fan on via the BCM/TIPM, nothing happens and I get no ground control signal at pin 86. The high-speed fan commands and works perfectly, so I don't think it is a communication issue. I went ahead and swapped the TIPM with a used one that has the exact same part number (didn't do any programming), but I ended up with the exact same problem. I also checked and load-tested all the main TIPM grounds and they are completely fine (didnt get to check powers but will if needed). To me everything is pointing to the TIPM but I am completely defeated by what looks to be a simple circuit and could use some extra eyes. Thanks.

Hey DarenO! I see you have P0480 stored in the PCM, but did you find any faults stored in the TIPM itself?

I found P0691 Cooling Fan 1 Circuit Low as a possible TIPM fault code. Its flow chart is pretty much exactly the testing you did:

lemon-manuals.la/Dodge%20and%20Ram/2014/...s/Diagnostic%20Test/

No programming is necessary with these. Just turn the key to on for twelve seconds then back off, which you've probably done by now.

The only other thing I can think of to try would be to navigate your scanner over to the TIPM itself and try the bidirectional fan controls there. If the low speed works while commanding it on from the TIPM, then that'd rule out the TIPM. You might also try another scan tool, if available. TopDon products are great, but they don't always work perfectly with Dodge/Chrysler/Jeep/Ram products.

Beyond that, I'd get another TIPM. 

Hi, yes i did have codes in the TIPM at times it would be both circuit high and low p0692 and p0691. I may have caused an extra one of them by disconnecting the resistor with key on but i know if I commanded the low speed on via the tipm one of them would set. The relay has no command when I active test with the topdon but i have an older autel and I will try with that. Might have to just end up going with a reman tipm

Gotcha. I think you just got (un)lucky with your first used TIPM. I might be tempted to gamble on another used before going reman, but that depends on availability.

Lst us know how it goes! 

Replaced with a used one from a 2019. Code is gone and fan works at low speed. I noticed I lost the function under the BCM where you can test the separate fan speeds, all I have now is Radiator fan PWM. Anyways it's working now, thanks for the help. Bad luck kicked my ass once again lol