BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Madmike on January 17, 2011, 10:24:54 AM

Title: 4106 Electrical question
Post by: Madmike on January 17, 2011, 10:24:54 AM
I have a 4106. The PO told me all the dash lights worked fine the last time he used them. I have had not luck making the Temp gauge, or any of the warning lights come up. ( Low Oil light does come on ) I don't think they have normal fuses like I am used too. Can anyone give me an idea of how to check to see if that is the problem? Also the fuel gauge that is out side of the bus only reads full when it is turned on. Got any idea? I only wish it was that painless to fill her up.
Title: Re: 4106 Electrical question
Post by: JackConrad on January 17, 2011, 11:58:14 AM
Buses use circuit breakers instead of fuses.  At least that is what was used when it was biult.  Many dash light problems are poor ground connections.  Make sure the dash panel has a good ground.  Jack
Title: Re: 4106 Electrical question
Post by: papatony on January 17, 2011, 12:12:09 PM
     Jack said it before I could.  If you take the dash out  ( Disconnect all power first) Remove the back panel there is a junction for most of the wires going to the dash. Make sure you have nothing to short and reconnect power . Check all post for power . That will let you know if the trouble is in the dash or the system . Get the manual for the 4106 you will need about a million times before you are thru.  But FIRST check the ground .  papa T
Title: Re: 4106 Electrical question
Post by: Barn Owl on January 17, 2011, 05:11:05 PM
Before I would pull the dash I would open the junction panel beside the left drivers leg and start troubleshooting there. GM buses are notorious for leaking into that junction box and corroding the terminals. Everything electrical starts, or passes through there. You will need the book to figure out what you are looking at, or what it looked like before someone made some undocumented "fixes".
Title: Re: 4106 Electrical question
Post by: gus on January 17, 2011, 07:49:39 PM
Repeating, you must have the Maintenance Manual and the wiring diagrams to get anywhere with this electrical system.

Any other way is just time wasting frustration.
Title: Re: 4106 Electrical question
Post by: pvcces on January 17, 2011, 09:29:25 PM
Don't be surprised if the fuel sender is just plain worn out. They are not bad to fix for someone who knows about fuel tanks in buses.

Tom Caffrey
Title: Re: 4106 Electrical question
Post by: Fred Mc on January 17, 2011, 09:42:02 PM
I put a new dash in my 4106 along with new gauges and the lighting for same. As stated all the wiring comes from the junction box beside the driver and each terminal is numbered. If you have a manual you can follow each wire from the numbered terminal to the gauge.

If you said that the po said all the gauges were working and now none are working it probably has to do with a ground.

Regards

Fred Mc.
Title: Re: 4106 Electrical question
Post by: Madmike on January 19, 2011, 10:10:23 AM
Thanks for everyones Ideas. I do have all the manuals and i will take off the pannel and see what i can see. I will post what i find.