Odinthewanderer

Thanks to everyone who responded with suggestions, especially Rich who must have spent hours analyzing my schematics. Long story short, after a lot of taking readings unplugging & plugging connectors, the problem was the park brake buzzer switch, apparently corrosion inside the switch shorted all three contacts together. Part # 06-31933-000 located just forward of rear axle on left frame rail. Craig

Rich, no signs of any rodents or chewed wires, so far all of the connectors I’ve disconnected (a lot) have shown no moisture or corrosion. I did take my pdf to a print shop & had them printed in 11 x 17 , it makes a little easier to follow, but still confusing. Craig

Rich, it did pop up overnight, it has been raining here a lot, it could be moisture related. I disconnected alternator, no change. I have isolated where I have voltage that I shouldn’t, if you look at sheet 1 in the lower left is IGN relay, at the normally open contact there is a fluctuating weak voltage of 3 to 5 volts. I think there should only be power there when the key is on. Thee wires join together just outside the relay labeled 52c . The stray power must be coming in from one of these wires, I pulled the 10 amp fuse shown just above this junction, no change the other two are harder to follow since they go back & forth through the large connectors on sheets 1 & 2. Craig D06-35775.pdf

Thanks for the replies, the model is WK36GD, last 6 of chassis j36087. i haven't had a chance to disconnect alternator yet, will try that later today. the chime that's sounding is the parking brake, normally it comes on if you put transmission in gear with parking brake on or let the vehicle roll in neutral, but is very similar to jacks down chimes which comes on if you turn key on & jacks are not fully retracted. It's hard to tell which one for sure because the relay buzzing is louder, ( i confirmed that it is the park brake chime). At freightliner's suggestion i have been disconnecting all connectors marked body builder one at a time , none of these had any effect, so i think my problem is on the chassis side. (see attached diagrams) . I have also disconnected most of the connectors that have a diode in them. Rich if you look at the diagrams it looks like the park brake relay & brake lamp relay are powered with key off ? Removing either of these get's rid of the problem. Thanks Craig __stnaffccw001.us164.corpintra.net_Service_Wiring schematics_D06-35775.pdf

Thanks for the quick reply, the voltage at the input of the parking brake relay is 13.2 (key off) . With relay installed, at the backup screen it’s flickering on & off too fast for an accurate reading ( goes from 0 to 5 ). I tried removing ignition & acc relays ( no change ). It looks like the brake circuits should be powered with key off ? I will try disconnecting A+ wire from alternator. Craig

Hi , I have a 2001 Winnebago journey, freightliner xc chassis. After being at a campground for a few weeks we were woken by a buzzing noise. With no key in ignition the backup screen was partially lit, the jacks down light was flickering, the transmission selector was blinking on & off, a buzzing from the dash area, and either the jacks down or parking brake chime was sounding. Disconnecting the chassis battery cable turned everything off. Freighliner sent me the chassis wiring diagrams, & I’ve done some troubleshooting. This is what I’ve found. The parking brake relay in the electrical compartment above the generator is the one that’s buzzing, removing it gets rid of all the problems, I tried a new relay but no change. When the parking brake relay is installed the neutral sense relay in the small relay panel above the engine also buzzes, removing this relay gets rid of all symtoms except the chime. The coach starts & seems to operate normally except the brake lights don’t work & the cruise doesn’t disengage when brakes are applied. I haven’t actually driven it because of the brake lights. Installing or removing the parking brake relay with the engine running doesn’t change anything except the relay buzzes. Thanks for taking the time to read this lengthy description. I thought someone may have had this same problem. We are currently doing some seasonal work so we don’t need to move the RV till end of December. I’m a retired aircraft mechanic & would like to continue troubleshooting on my off days. Thanks for any suggestions. Craig