Selinoid

[farmingdad]

Can any tell me were chassis selinoid on a 08 sig

[enblethen]

This is the common battery disconnect relay
Intellitec Big Boy

[Groover]

I am guessing that by "big boy" your are referring to a Trombetta relay like the one below that is used to connect the house battery pack to the engine battery pack so that both packs can be charged from a single outside source. It may be energized whenever there is a sufficiently high voltage applied to either battery pack to indicate that charging is available.

Trombetta relay

My Trombetta did get very hot to the touch while the coach was plugged in and failed twice. I disconnect the trigger from the house battery pack and put a battery maintainer on the engine battery pack. Now my Trombetta lasts much longer. The link I shared has by far the best price that I have ever seen on a Trombetta.

I am guessing that the relay that keeps failing was not meant for continuous use, most starter relays are not. Either that or you passing too much power through it. I would try to figure out its function and whether the trigger is stuck on improperly if you have the wrong relay or maybe just and undersized one.

It could be a relay for power to the house. My coach has a button that remotely kills all 12v power to the house for storage or whatever other reason comes up. That would definitely require a continuous duty relay.

What are the symptoms when it fails?

[William_B]

The Big Boy is normally hot to the touch, but certainly not hot enough to ruin another solenoid. There is some other problem, and you still haven't said what solenoid??

[enblethen]

Have you had a chance to look into problem?
Here is a thought.
Check to see what system the Big Boy latching relay disconnects. Then identify the other relay that keeps failing. Larger 50 amp rigs commonly have 200 amp relays where smaller rigs utilize 100 amp. Installing the wrong amperage can cause premature failure.
Locate the starter, trace the large battery cable back to it's source.
Trace the small wire from starter back toward the front of the rig.

[enblethen]

Maybe the "ignition solenoid" is the starter relay and the starter is not disengaging.
Might have to trace some wires or get the wiring diagram for the rig.

[YC_1]

farmingdad wrote:
I’m try to help a friend work on his. The big boy in the rear run box stays hot all time to touch and the ignition selonond beside it keeps going bad

If the person has the rv plugged in or plenty of solar that solenoid can run very hot to the touch.

The amount of heat given off should not certainly harm another solenoid nearby.

The person needs a voltmeter to diagnose.

[farmingdad]

I’m try to help a friend work on his. The big boy in the rear run box stays hot all time to touch and the ignition selonond beside it keeps going bad

[Ivylog]

A DP doesn’t have a neutral safety switch...will start without air in the system and with the parking brake on or off. I do not know of a diesel starter that doesn’t have the solenoid mounted on it.
I did look in my front run box and there is not a fuse for the starter there. I previously posted that there is a fuse in the rear run box on the board that lets you start from there.

[enblethen]

In other posts, OP talks about a starter solenoid. This will depend on what motor the Monaco is equipped with. He also says an 08 Signature and does not specify engine.
Some have the starter solenoid mounted directly on starter.
Some rigs have a starter relay in compartment under driver's area on the exterior of the rig.
I would add that there should be a neutral safety switch and possibly one connected to the parking brake system.

[oldave]

There are more than one type of solenoids. What are you working on? The leveling or?