Community Forums

Smitchell · 07-03-2022, 06:35 PM

We have a 2018 Newmar Ventana that we were planning to take on a 28 day trip. We were supposed to leave this morning but when we did our light check, we discovered we don’t have rear brake lights, rear turn signals or flashers. The dash AC is also out. We were able to take it to the local Freightliner dealer and they diagnosed a bad chassis module. We have already replaced the PDM and the PDM wiring harness as recalls. The tech said power was going thru the PDM but not through the chassis module. It seems strange to me that the symptoms we are having are the exact same as we had when the PDM was bad and needed to be replaced. The lights and AC did work last month when we we on a 3 day trip.

We were told we needed a new chassis module. Of course there are none to be found in any Freightliner distribution center anywhere and there are no expected dates when one might be available.
After talking further with the tech he thought we could work around the lights issue with portable lights plugged into the RV’s tow receiver. He thought power should get to it as the PDM is supposedly functional. I don’t know anything about that, just repeating what he told us. We tried this suggestion but the portable lights would not come on when plugged in to the RV tow receiver.

So….do we go back to Freightliner and try installing a new PDM even though the tech assured us that wasn’t the problem?
Does anyone have a suggestion for a wiring work around to get power to the RV trailer hitch so we can use the portable lights and try to salvage this trip?
Any other thoughts/suggestions you have would be greatly appreciated.

We have been planning this trip with friends for over 6 months and we are so very disappointed.
Thanks in advance for your time and help.
Linda

153stars · 07-04-2022, 07:54 AM

You could do like they said but are you also towing. That might take bit more work . The biggest or double up trailer lights and good two sided tape could work. Or if you wanted to disconnect current lights and wire into trailer output. Of course you better test that trailer output first. My old side radiator MH wouldn't be too difficult to modify under the rear cap. External mounting trailer flat wire to current light might be easier. If they used common auto plugs to lamps you may even be able to source plugs at auto parts store.

Smitchell · 07-04-2022, 09:18 AM

Thanks for taking time to respond. The problem is we are not getting power to the rear lights or to the RV tow plug. This must be due to the faulty chassis hub module, (a part that is out of stock everywhere).
2 different techs have told us we should still have power at the tow plug because that power doesn’t run through the chassis hub module, but it must.
We were looking for a temporary work around to get power to the tow plug so we could use portable lights to provide break lights and turn signals to the MH. Just so we could get on the road while we wait for the back ordered chassis hub module. We are not towing a vehicle.
I was hoping someone in this RV brain trust would have a suggestion for running power to the tow plug that would bypass the chassis hub module.
Have a great Independence Day,
Linda
2018 newmar ventana

windsorbill · 07-04-2022, 09:43 PM

Quote:

Originally Posted by Smitchell

Thanks for taking time to respond. The problem is we are not getting power to the rear lights or to the RV tow plug. This must be due to the faulty chassis hub module, (a part that is out of stock everywhere).
2 different techs have told us we should still have power at the tow plug because that power doesn’t run through the chassis hub module, but it must.
We were looking for a temporary work around to get power to the tow plug so we could use portable lights to provide break lights and turn signals to the MH. Just so we could get on the road while we wait for the back ordered chassis hub module. We are not towing a vehicle.
I was hoping someone in this RV brain trust would have a suggestion for running power to the tow plug that would bypass the chassis hub module.
Have a great Independence Day,
Linda
2018 newmar ventana

Did you test the rear plug with the ignition on? Only other thing to check are the fuses, but I don't know where those are on your coach.
https://images.app.goo.gl/TsRNZBq9bFzvBPtS7

Toribk · 07-05-2022, 11:08 AM

Smitchell,

I'm uncertain if your coach is on a Freightliner chassis, but mine has two relays in the main Freightliner fuse panel that govern the 7 way plug and the tail lamps.

They are depicted on the diagram inside the cover.

Just something else to check as your troubleshooting.

Sent from my SM-G955U using iRV2 - RV Forum mobile app