Error P1491 Radiator Fan Control Relay

[jonirt]

I'm getting a P1491, radiator fan control relay control circuit, error code on my 2002 Ram 1500. When the engine light came on, the A/C began blowing warm air when sitting idle. It blows cool air when accelerating. Is this something a dealer has to fix? Suggestions?

[CrewChief44]

I had the exact same problem on my 02 RAM.. I know this is an old post, but done a search to see how many others had this error code. I was told it was the condenser fan and the dealer wanted over $400 to replace the fan... I said hold up on that repair.. I'll replace it myself... Bought a new fan, plugged it in before installing, still didn't work. It ended up being a 15 cent fuse and not a $400 fix!! Needless to say I'm done with that dealer...
Anyway, I ended up finding out the problem is actually with the shroud around the fan. In the winter if it gets any water in the shroud it will freeze and lock the fan, thus blowing the fuse. You can either buy a redesigned $200 fan and shroud, or simply drill drain holes in your shroud so water will drain out.... thought it was worth a post!

[canseco24]

This was my problem as well. Had the dealer telling me to bring it in...Said no I'll just try to figure it out myself. He had also said it could be the fan. But low and behold after reading your post I checked the fuse. THAT WAS IT! Thank you so much. You are a life saver.

[lovemyfreakingtruc]

go to google and type in dodge pick-up 4x4 2001 and get the trouble shooting manual.

[cannon73]

I had this same problem with my '02 Ram. And it was the fuse for the fan. Very quick fix. I believe it it fuse #39.

[pretz509]

I spent the morning at Schucks getting my Ram diagnosed only find out that my radiator rely was "the prblem". Well as you all have probably figured out, there is no after market relay nor does the fuze box list the relay either. So I had an idea to go online and see what a forum had to say. When I read the forums and found out that others had the same problem I was a happy camper. But even got better when the fuze number was listed. So I went outside and popped the hood and pulled fuze #39 and there it was, blown.... I went back to Schucks, bought fuze and even briefed them on the problem with a hopes that they would store it in long term memory for future customers. Once i installed the fuse I pulled the neg terminal for a few minutes amd all is well. So I would like to thank all of you for saving me $400+ bones. And I am now a forum reading guy.

[Astrotram]

OMG, I had the same DTC and had found that no one new what it meant. I had an appointment with the dealership in the morning to have it diagnosed because I couldn't find a straight answer. You were right on the money and saved me a few $$'s. "Radiator fan control circuit problem (may be solid state relays as well as other circuits)" was the best answer I had found. Replaced fuse and is fine. Thanks so much.

[trudy29]

I had the same error code (P1491) and found this forum. Thank goodness. Sure enough it was the 39 fuse. I replaced the fuse, took Dodge Ram back to Auto Zone and that cleared the code. Thank you.

[westislandbrewer]

Hello,

I was getting the same error message. I went to a scrap yard and obtained a used relay module for $10.00. A new one (MOPAR) is $100.00 up here in Montreal Canada. I replaced it with mine and I have been trouble free for 4 months now. I can't say this is your problem but this worked for me.

Regards,

Philip Moogk

[God fearing man]

opcorn: Here goes a HUGE thanks to all that posted the fix for that P1491 DTC code.For sure I will be eating waaaay more than popcorn with all the $$$$ that I saved following your advice. Many thanks, indeed! Went to my local AutoZone, bought the little fuse to replace # 39, as you guys stated, told people at the auto parts store to make note of this easy fix, came over to my place, using my pocket OBD II scanner, erased the code, ran my Ram for some minutes, NO CHECK ENGINE LIGHT anymore. Needless to say that you were 100% right about fuse # 39 being blown. Again, THANX!!!!!!!!!!!

[PAR4DIY]

lay on a big high 5 from me. Layoff's abound and furlough a definate, I need to keep costs to a minimum and both cars working as the wife is back working to keep the checkbook balanced. You guys ROCK! fuse 39 was definately blown.

[alphadog1959]

Just wanted to say "Thank you for all your posts". I will check the # 39 fuse and pull the batterey cable to reset the check engine light. I was told that before I can get my smog test run I need to drive the truck a 100 miles. is this fact or fiction ? Thx

[platinumj]

the internet is a wonderful thing, thx to all who posted about this subject,

saved me a huge headache

[Empress777]

Whew! I followed your instructions and low and behold....a blown #39 fuse. Tomorrow I will replace it with a new one. My quesstion is what caused the fuse to blow? It is eight years old but so are the other fuses; could it be a short somewhere in the fan circuit? Has anyone seen a replacement fuse go and followup on the cause?

[dannyvpa]

This message is accurate. I just had the same problem, same code P1491. My truck is also 8 years old and never had a fuse blow, but you have to think sooner or later they will blow because of age. Especially because that component is cycled quite a bit.