P0542 Code and CEL

[clovisb31]

Hello all,

My 2015 2500 Cummins set a P0542 code and Check engine light a week ago. I scanned the code, reset it to see if it would re occur . It came back on yesterday. I scanned again and just found Freeze frame data for the same P0542 but it did not set a code, even though it lit the CEL. Looks intermittent. This code is """ P0542- " Intake air heater control circuit 1 high""". I do not , as yet , have a service manual for this truck. Does anyone know the physical location of the Air Heater relay in the engine compartment? I need to start checking connections as a first resort.

Any help is appreciated.

Thanks!

 

[Bob4x4]

You are looking for what will look like an old style Ford starter solenoid near the passenger side Battery

 

[clovisb31]

Thanks Bob4x4. I'll be checking for that and the connections made to it. I am hearing even a slight loose connection can set a code on these RAM trucks.

Wonder if they bought all of Ford's left over starter solenoids to use in the 2015 truck builds . heh !!

 

[Ram_Fan]

clovisb31 - anything to update on this? I recently got the same trouble code on my 2015 2500. Tried clearing it, but it came back. No apparent issues with anything, just the annoying CEL. Any additional info you can provide would be greatly appreciated.

 

[clovisb31]

Yes Sir ! Ram_Fan ,

On my last post it was suggested I check the connections on the "Ford style" relay for the grid heater , located on the passenger side below the battery. It has push on style connectors. These get goofy with corrosion or temperature swings causing a poor connection.

What I did was pull them off the little studs they push on to, check for corrosion (none that I could see on mine), clean them with a small brass brush if needed (I didn't need to ). Be careful of the large 12 volt cable when cleaning. Apply some dialectric grease to the little studs and push the connectors back on. I have had no problems since. You may need to erase/reset the code with your scan tool. I did and it has never come back.
Knock on wood !!

If the above does not solve the CEL light coming on , then you may really have problems in the grid heater/ relay or circuit itself.

Take care !

Shane in Sanger.

 

[Ram_Fan]

Thanks! I'll give this a shot and will post back here with the results. Fingers crossed. Appreciate the quick reply!