Thread: p0480 and p0481 need help

I have the p0481 code as well. Anybody know what this could be? I replaced the 2nd fan even though I didn't think it would help. It didn't.

Help Mike and me please!

need help with that p0481 code, also i have a p0102 code also and we just changed the maf sensor?? please help 2000 pontiac grad prix, 3.8 supercharged

Pull the fan relay wirh the key turned on. With a test light check for power. one of them should be hot all the times. If not check your wiring. If you have power run a jumper wire to the prong across from it(assuming it is the big square relay) which should turn on the fan-if not you have a wiring issue after the relay. if it comes on run the car till its warm enough that the fans should kick on. check the other two prongs one should be a ground and the other should be power suplied by the temp sensor/switch. if your not getting power its between the sensor, pcm, and wiring.

I solved my P0481 code problem.

I replaced the second cooling fan and both relays and it didn't help. I removed the cover from the second relay and when I squeezed the armature plate and closed the contact the fan worked. So I decided that the wiring must be bad.

I had a sneaking suspicion that there was a wiring issue but was too lazy to want to start diving into the wire loom. I procrastinated way too long and wasted a lot of time, money, and effort.

A little background: When my car was about a year old there was a recall for the alternator. I don't know what the recall was for but around the same time the original battery cracked. Maybe it was getting overcharged and that's why it happened. In any event acid got all over the place. I cleaned the area with baking soda and water and thought everything would be okay.

But apparently acid had gotten down into the corrugated conduit and I didn't get it out adequately. After a few years the acid seeped into two wires that just happened to be for controlling the relays. The wires had sections that were bulged and broke when I flexed them. Inisde, the copper had turned into a green dust. I was elated to find these bad wires.

A replacement harness is priced at almost $1000 so I cut out the bad sections, found some colored wire in my stash that was pretty close (it pays to be a pack rat if you know where to find your junk), and spliced them in. I cleaned the rest of the wires with more baking soda and soaked them with 303 protectant to prevent further breakdown and wrapped it all back up.

I cleared the code and it didn't come back and the car was finally able to pass the air quality test! YAY! There's nothing like fixing an electrical problem to make you feel like a hero.