I have a 97 Dodge Ram 3500 DRW Cummins diesel w/factory tow package and am pulling a 27 foot fiver.
My question started on the RV forums with the query; should I disconnect my truck connector when hooked to either shore power or using my external generator?
Many of the replies referred to a "tow relay" that only operates when the truck is running.... that is what is supposed to connect the truck's battery power to pin 4 of the connector to charge the house battery in the trailer.
Well, my service manual for 97 does not show that the tow relay works in that manner. The tow relay operates via the headlamp switch to provide power to the trailer's running lights and license plate light via the connector. I checked this out with my multi-meter and it does what the manual states.... in fact, the tow relay operates ANYTIME the headlight switch is in park or on position. I also see NO sign of any type of isolator in the circuit.
Can someone confirm that Dodge only uses a tow relay for that function which I have described? I would hate to wake up on an interstate rest stop with battery problems in the Dodge.
Thanks.....