2004 Dodge RAM 1500 PU Check Engine Condenser Fan problem

dodge
ram
1500

#1

Hi There! I’ve got a bit of a sticky wicket here - kinda gets complicated so stick with me;



The check engine light started lighting up on our 2004 Ram 1500 pickup, and our mechanic (who I like very much and trust completely) ran the code and it came up with a bad condenser fan. He checked the fan and it runs fine when power is jumpered to it, and the fuse and relays that drive it are both OK, but apparently the power control unit won’t turn it on. He told me I’d need to take it to a Dodge dealer since Dodge won’t release enough information for him to troubleshoot further. I took it the dealer; they ran the diagnostics (for $110) and said it was a bad condenser, and recommended replacing the condenser and shroud (with fan) for a mere $900. With that diagnostic in hand, I took it back to my guy, who said “prob’ly not, but maybe there’s something I don’t know…” so he put a new condenser fan in, and in the process pulled the entire condenser unit, drained it, checked it, and put it back in - condenser is definitely OK, and new fan unit is installed, but get the same problem: Check engine lights, and condenser fan won’t turn on.



I’m loathe to take it back to the dealer, but don’t really know where else to turn at this point. I’m in Burbank, CA.



Anyone have any ideas?



Many thanks in advance!



Rich B


#2

I’m going to give an “exploratory” reply to bump this since I can’t tell you what I think is really happening. First, if you provide the actual, specific error code (e.g. “P1234”) that helps a lot. Second, your mechanic made sure the fan ran. And he checked the fuse and relays. What about all of that wiring in between? The power still has to make it from the fuse/relay to the fan. I wonder what would happen if, for testing purposes he ran a set of wires directly from fuse/relay to the fan.

In the midst of this did anyone mention any “technical service bulletins”? A couple of people here have access to data bases and often come up with them for certain problems. Perhaps one of them can come by - or ask your mechanic if he searched for them


#3

Thanks - I don’t have the actual code number, but the dealer’s description is: “drb 3 scanner found code low speed fan relay circuit causing ac to blow warm air causing check engine light to come on”. Of course, AC blows cold air (just no condenser fan so dangerous to turn on AC).

Yea, my mechanic thinks it’s a wiring problem in the power control unit, but according to him that’s a black box that is not serviceable by anyone except a dealer…

thoughts?

TIA,
rich


#4

The PCMs are not serviceable by everyday mechanics, but they can be replaced and there are companies that do specialize in car computer services. Actually if you happen to find any common problems for these vehicles (TSBs), and the issue can be repaired, you’ll probably find companies offering repair/rebuilding. Sometimes its not very expensive at all. You can probably find out with 5 minutes eBay.


#5

Check the relay and its fuses. See picts.


#6

Thanks to all for the replies so far! Yes, fuses and relay have been checked and are good. What I don’t know is if power is being applied at the input to the power module and not making it out the other side, or if it’s simply never being applied. I’ll call my mechanic tomorrow to see if he was able to trace it that far.

What I’d really like is to find a specialist in my area who can accurately diagnose and repair without going back to the dealer!

Anyone know of someone in this area?

Thanks!
rich


#7

Here is the Mechanic locator. http://www.cartalk.com/content/mechx/find.html


#8

OK, spoke to my trusted mechanic; Says that he diagnosed it down to power definitely going through Condenser Fan Fuse, and control voltage getting to Condenser Fan Relay, but no fan power getting to the input to the relay switch (IOW control voltage is good, but high current not getting from fuse to relay), which means it’s somewhere in the black box of the fuse/power module (integrated power module) between the fuse and the relay. He didn’t want to just jumper it, and felt that a dealer should fix it since it’s a black box and he doesn’t have the schematic for the module itself, but I don’t trust my dealer since they’ve misdiagnosed once and wanted to charge me $900 for an incorrect repair. So now I’m looking for someone who’s good with electrical/electronics on a Dodge 1500 in my area. Mechanic finder doesn’t get that fine-grained, and all it does is list a ton of mechanics around here, all with 1 or 2 or 3 reviews.

Any suggestions?

Thanks!
rich


#9

OK, so FWIW if anyone happens to search on this; Problem is solved - turns out it was a bad wire at one of the harnesses directly below and feeding the IPM. An electrical guy who I found on Yelp with good recommendations managed to find it after tearing into the IPM a couple times.

Dealer of course was completely wrong and would have charged me $900 to replace a perfectly good condenser unit. Final repair was $250.

Thanks for all your help.

rich