MIL Lit Up but No DTC's

[TimothyLong]

Just had something odd happen on my wife's O4 Ram 2500. The MIL was lit and when I hooked my OBD2 scanner to it, the scanner showed the MIL as being on, but it said that there were no DTC's to recover. I disconnected the scanner and tried it again, got the same result. Then I shut the engine off and turned it back on and the MIL cleared itself. She said that it first came on last night when she went to work, but everything seemed to be okay. All the gauges looked fine. The engine is totally stock, no mods of any kind. Anybody have any ideas?

 

[AllianceDiesel]

cycle the key three times and see what codes comes up

 

[TimothyLong]

I forgot about that little trick. It came back with P0480 - Low Speed (No. 1) Fan Relay Control Circuit. Need a new fan relay?

 

[AllianceDiesel]

swap relays with another one like your horn relay and see if the horn works after the swap

 

[TimothyLong]

At the risk of sounding like an idiot, where are those relays located? I was out changing oil and filters in both of them today and I couldn't find the relays. The only thing I saw in the power control module was a fuse for the horn, but no relays. I'm sure that they are located right in front of my face. The exact spot where I wouldn't be able to find them!



Thanks!

 

[AllianceDiesel]

i would have to look they might of got rid of the relays can't remember, I will do some checking

 

[TimothyLong]

Let me know if you find anything. It's running fine with no MIL so far.

Thanks!