Mystery part related to rear door buzzer?

[xrw44]

I'm trying to disable the rear door safety feature and start my bus. I have removed the interior door latch. I don't have the cylindrical relay I see in several videos.
The part pictured has a wire to a "buzzer" breaker and 3 other wires going into cable marked "door buzzer..."

[Clouse House]

Originally Posted by xrw44

I'm trying to disable the rear door safety feature and start my bus. I have removed the interior door latch. I don't have the cylindrical relay I see in several videos.
The part pictured has a wire to a "buzzer" breaker and 3 other wires going into cable marked "door buzzer..."

That part should make a buzzing noise if the rear door is open when the bus ignition is on. I don't think it's the part you are looking for. But the trigger for that should be the same as the trigger for the safety feature.

[ewo1]

Originally Posted by xrw44

I'm trying to disable the rear door safety feature and start my bus. I have removed the interior door latch. I don't have the cylindrical relay I see in several videos.
The part pictured has a wire to a "buzzer" breaker and 3 other wires going into cable marked "door buzzer..."

Find the two wires that went to the push button type switch that was on the door handle, short them together and then see if the bus starts.

By shorting them together you are telling the bus the switch is in operation.

Take a look over at this thread, post #2 and download "Front & rear buzzer".

I know your bus is a Thomas but the wiring should be similar if not the same.
At the very least at least you'll be able to figure out what is going on with your bus, I hope!

You'll see the switch wiring and the 3 wire buzzer wiring too.

[xrw44]

The bus is 97 Thomas international 444ci puller

[xrw44]

Thanks ewo1. You said,
"Take a look over at this thread, post #2 and download "Front & rear buzzer".
I don't see a link to a thread.

[ewo1]

Originally Posted by xrw44

Thanks ewo1. You said,
"Take a look over at this thread, post #2 and download "Front & rear buzzer".
I don't see a link to a thread.

LOL...click on the words "This Thread", that's the link. It is underlined.

[xrw44]

I don't have the latch but I found this pic of the wiring before I removed it. The white, yellow (B32) and blue wires are now protruding out of the new wall. I have tried grounding the yellow wire and there was no change.

Per haps we can figure this out? I see too many blk wires!
Blue goes where?
Yellow is nutted to a blk that goes where?
The plunger switch has 2 common white wires and 2 common blk wires. Does the switch have additional connections? When the door is closed, the plunger connects the wht and blk wires?
A body ground is connected to a wht and a blk wire, from the switch ?

[ewo1]

Originally Posted by xrw44

I don't have the latch but I found this pic of the wiring before I removed it. The white, yellow (B32) and blue wires are now protruding out of the new wall. I have tried grounding the yellow wire and there was no change.

Per haps we can figure this out? I see too many blk wires!
Blue goes where?
Yellow is nutted to a blk that goes where?
The plunger switch has 2 common white wires and 2 common blk wires. Does the switch have additional connections? When the door is closed, the plunger connects the wht and blk wires?
A body ground is connected to a wht and a blk wire, from the switch ?

Grab a piece of paper and try to draw out the circuit the best you can.
The push switch basically will break the circuit when the door is open and that is why the bus won't start. When the contacts are closed the circuit will function and bus will start.

You picture does not tell me much so your gonna have to slow down and take this step by step, it is quite easy. Got more pics?


Your very first pic, where was that yellow box located and do you have pics of that?

What transmission do you have in the bus? depending on the trans you might be able to "disable" the door lock circuit another way, but don't get excited just yet.

Look at the diagrams that I pointed you to, most bus circuits will be either the same, or very close to the diagram.

Oh yeah, don't disconnect anything els if you don't know what your doing.
Take pics, ask questions first, then and only then, remove or cut wires!

[pippy]

Just recently picked up an 07 ce300. We also had a no start issue at the same time the emergency door alarm and light were active.
What i discovered is that all the emergency windows and exits were tied into the buzzer and light, but not on the starter interrupt circuit. The actual no start was due to the dead bolt on the bottom of the rear door having a sticky switch. If the door is locked from the inside the bus would not start. Bypassed the switch and life has been good.
Built motorhomes and firetrucks for 20yrs as the electrician. So very familiar yet running blind without the full access to schematics and computers that i used to have.
Best of luck!