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Just got a P0480 code out of nowhere after a startup. Temperatures seem fine while driving, rarely goes above 220 unless it's 90+ out. While idling, if it gets above 220 the fans kick on. Any ideas?
Sorry to hear you're having issues with your cooling fans...P0480 is your cooling fan #1 and the PCM is looking at the cooling fan 1 circuit highlighted in yellow...if the voltage there is incorrect the DTC will set but the first thing I should ask is do you have a 12 volt test light ??...the next thing I would do is check fuse 49 and then swap relay 45 (cooling fan 1) with say the horn relay...erase the code through the DIC and then see if the DTC comes back...BTW, what exit ???...LOL !!!...when the car is first started with the AC on both cooling fans operate at low speed...cooling fans 1 is energized and so it turns on the left fan and cooling fan relay 3 works and the right cooling fan operates.
Thanks for the info! I will check the fuse/relay and see if I notice anything. I already have a note out to my shop near me (Stage1 Auto) and will try to get the car to them next week.
Interestingly enough, I rarely run the AC in my car because the driver side actuator is funky, and yesterday, I was running the AC and after that I started having the issue...Stay tuned!
Thanks for the info! I will check the fuse/relay and see if I notice anything. I already have a note out to my shop near me (Stage1 Auto) and will try to get the car to them next week.
Interestingly enough, I rarely run the AC in my car because the driver side actuator is funky, and yesterday, I was running the AC and after that I started having the issue...Stay tuned!
OK, we will let your shop diagnose this issue and I hope they are not just a parts changing shop…let's us know what they find if anything.
They said they ordered a fan control module from the dealer, so it exists!
Ok, if they "THINK" it's the fan control "module" which the car doesn't have I think they don't have any idea of what they are doing...the circuit is basically fuses, 3 relays, 2 fans and a PCM which controls the fan circuit...I would tell them whatever they change that may not fix it you will "think" about paying them !!...fan controllers are on the C6's.
How about just swapping the horn relay with cooling fan #1 relay #45 then clear the code through the DIC and drive the car a few times with the AC on and see if the P0480 returns...you may just have a bad relay.
Last year I helped a friend with troubleshooting a P0481 alarm on a 98 mod.
Fans where working fine and the cooling temp was OK but the still the P0481 alarm appeared .
As the schematic shows the PCM is controlling the fans relays by grounding these three relays in sequence .
On low speed the relay 45 is grounded and both fans run on low speed due to the fans are coupled in serial .
When the PCM ground C1:43 the voltage on this PCM input drops fraom 12 volt to 0.1-0.2 volt .
The PCM is (shall) sense this voltagedrop from 12 to 0.1 volt internally .
On my friends car I measured the voltages on the PCM input and the voltages was perfect but still the P0481 alarm appeared :
I figured out that the internal sensing circuit in the PCM was damaged and adviced my friend to get a new PCM in order to get rid of this P0481 alarm .
After he get a "new" which I installed the alarm dissappeared and problem was solved .
I therefore think you may need a need PCM to solve this problem but a closer look to these signals like I did should be carried out first to verify proper operation of these cooling relays on the PCM inputs
Last year I helped a friend with troubleshooting a P0481 alarm on a 98 mod.
Fans where working fine and the cooling temp was OK but the still the P0481 alarm appeared .
As the schematic shows the PCM is controlling the fans relays by grounding these three relays in sequence .
On low speed the relay 45 is grounded and both fans run on low speed due to the fans are coupled in serial .
When the PCM ground C1:43 the voltage on this PCM input drops fraom 12 volt to 0.1-0.2 volt .
The PCM is (shall) sense this voltagedrop from 12 to 0.1 volt internally .
On my friends car I measured the voltages on the PCM input and the voltages was perfect but still the P0481 alarm appeared :
I figured out that the internal sensing circuit in the PCM was damaged and adviced my friend to get a new PCM in order to get rid of this P0481 alarm .
After he get a "new" which I installed the alarm dissappeared and problem was solved .
I therefore think you may need a need PCM to solve this problem but a closer look to these signals like I did should be carried out first to verify proper operation of these cooling relays on the PCM inputs
C5 p0480
