Thanks so much for the speedy reply.
It's early morning here in the UK and I was out at the truck trying to find out the problem.I tried the pin 15 on the FCM to the earth on the park relay pin 85. You were correct btw about the terminal numbers.
I didn't have an earth either. Also, when I jumpered terminal 85 to ground...........yep......you guessed it, the lights came on.
So, I thought as you, that's my IPM up the spout.
Anyhow, what I did is, removed the FCM and gave it a good spray in the contacts both on the FCM and the IPM with WD40. I then connected them and took them apart 4 to 5 times, to clean off the contacts, before making a final fitment and screwing the module back onto the IPM.
I then sprayed the big connector with all the wiring underneath the park relay, both on the connector itself and the bottom of the IPM where it plugs into.
I did all this with the battery neg removed.
I connected everything back up and it all works.
The only thing I can think of is that the WD40 has reduced a high resistance in a contact or something.
I believe the FCM can be very sensitive to high resistance circuits, as can the rest of this 3rd generation computer stuff.
I rechecked pin 15 FCM, to the park lamp terminal 85. Still open circuit.
So, looking at the circuit schematics your quite right in assuming that you should have an earth path there, but in reality, there doesn't seem to be. I put my multimeter on several different ranges to try and get a reading, with no joy at all.
So, If you haven't already done so Victor, give it all a good spray down with WD40 and reconnect everything and give it a whirl.
Hopefully, it might work for you.
Best of luck and cheers for all the help mate.
P.S I'm posting this on the forum as well to help out the other guy xfirechief.
03 Dodge Ram 1500 Hemi SLT
5.7 ltr QC sb 4x4
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