For download - Thomas MVP-EF wiring diagram!

[dbsoundman]

Hi all, I reached out to the Thomas dealer that originally sold my bus, and they were kind enough to contact Thomas directly and get a generic wiring diagram for my bus. They said there aren't specific schematics available, but this is still VERY helpful to me. My bus is an 06 with a Cat C7, but the schematic mentions the Cat 3126, so I imagine this will work for older buses as well. Note that this applies to the MVP-EF model, I don't think it will apply to the Saf-T-Liner or an MVP-ER (rear engine). The biggest way to tell the two bus models is the Saf-T-Liner usually has round headlights, but I don't know if that's true for all model years.


Link: https://www.skoolie.net/forums/attac...1&d=1630076887

[stlthe]

Thanks for sharing this schematic. I'm replacing my instrument cluster&%#k with a NOS unit (ebay) and came across a suspected speedo wiring discrepancy which this document confirms. Black wire 12 is routed through the 8-way connector on my bus, instead of the 6-way, meaning if I just plug in the dash harnesses at best things are broke.

I have not examined all the harnesses for compliance to the diagram, but the new cluster does conform.

This is hard work with the drivers seat in place.

[dbsoundman]

Originally Posted by stlthe

Thanks for sharing this schematic. I'm replacing my instrument cluster&%#k with a NOS unit (ebay) and came across a suspected speedo wiring discrepancy which this document confirms. Black wire 12 is routed through the 8-way connector on my bus, instead of the 6-way, meaning if I just plug in the dash harnesses at best things are broke.

I have not examined all the harnesses for compliance to the diagram, but the new cluster does conform.

This is hard work with the drivers seat in place.

I'm jealous you found a new cluster, mine just went out and I'm hunting parts yards to find one that hopefully works.

[stlthe]

I must consider myself lucky, I even found an oem replacement for my broken air pressure gauge. Now if i can fix the leaks, source a doghouse and air ride seat along with some underbus storage i'll be in great shape.

I have the old style dash, and the price was right. https://www.ebay.com/itm/124604721105.

My original was functioning, but was falling apart when i got it. i kid you not i had to use zipties and plastic 6-pack can holders to keep things in place. A true eyesore. Now the cluster will be the focal point of the whole project

I have been using the bluefire app as a digital dash, for me it works well so far.

What HP is your C7? I have the 210hp, lots of hours but only 120k on the odometer.

thanks again for the schematics. I cant decide if i should change the cluster wiring to match the bus, or change the bus to match the diagram.

Evan

[dbsoundman]

Originally Posted by stlthe

I must consider myself lucky, I even found an oem replacement for my broken air pressure gauge. Now if i can fix the leaks, source a doghouse and air ride seat along with some underbus storage i'll be in great shape.

I have the old style dash, and the price was right. https://www.ebay.com/itm/124604721105.

My original was functioning, but was falling apart when i got it. i kid you not i had to use zipties and plastic 6-pack can holders to keep things in place. A true eyesore. Now the cluster will be the focal point of the whole project

I have been using the bluefire app as a digital dash, for me it works well so far.

What HP is your C7? I have the 210hp, lots of hours but only 120k on the odometer.

thanks again for the schematics. I cant decide if i should change the cluster wiring to match the bus, or change the bus to match the diagram.

Evan

Oh wow that is an old dash, I've never seen that style. Good to know I'm not alone though, I see LOTS of folks complaining about International dashes but no so many with Thomas issues.


I think my C7 is the 230hp - whatever the max was in 2005. I forget my hours but when I averaged out the odometer miles per engine hour I ended up with about 20 mph, so not too bad.

[tiptop07]

Originally Posted by dbsoundman

Hi all, I reached out to the Thomas dealer that originally sold my bus, and they were kind enough to contact Thomas directly and get a generic wiring diagram for my bus. They said there aren't specific schematics available, but this is still VERY helpful to me. My bus is an 06 with a Cat C7, but the schematic mentions the Cat 3126, so I imagine this will work for older buses as well. Note that this applies to the MVP-EF model, I don't think it will apply to the Saf-T-Liner or an MVP-ER (rear engine). The biggest way to tell the two bus models is the Saf-T-Liner usually has round headlights, but I don't know if that's true for all model years.


Link: https://www.skoolie.net/forums/attac...1&d=1630076887

Thank you for this! It’s been hard to find any good diagrams for these models! By any chance, did you remove your interlock system? I’ve (much like everyone else that’s never dealt with these things) gotten myself into trouble. I see a lot of threads saying to jump the interlock relay, but my biggest problem is that I can’t seem to figure out exactly which relay it is, whether it’s in the passenger side relay box or on the external drivers side. Thanks for any input!

[dbsoundman]

Originally Posted by tiptop07

Thank you for this! It’s been hard to find any good diagrams for these models! By any chance, did you remove your interlock system? I’ve (much like everyone else that’s never dealt with these things) gotten myself into trouble. I see a lot of threads saying to jump the interlock relay, but my biggest problem is that I can’t seem to figure out exactly which relay it is, whether it’s in the passenger side relay box or on the external drivers side. Thanks for any input!

FS65 is a conventional model right? My bud is a transit front engine so I don’t have anything on the passenger side. Either way I would suspect any interlocks are under the drivers side window in that compartment. Thomas didn’t really add much of anything accessory wise to the front or underside of the bus, it’s basically all in that side compartment. Somewhere in the spaghetti…

[tiptop07]

Originally Posted by dbsoundman

FS65 is a conventional model right? My bud is a transit front engine so I don’t have anything on the passenger side. Either way I would suspect any interlocks are under the drivers side window in that compartment. Thomas didn’t really add much of anything accessory wise to the front or underside of the bus, it’s basically all in that side compartment. Somewhere in the spaghetti…

Yeahh, I have been going crazy tracking everything down. The only this I can have surmised this far is that the starter relay is on the pax side, and jumping that relay hasn’t helped, I’ve gone as far as jumping everything I can think of, and none of it seems to allow the bus to start. When I jump the solenoid it starts right up.. strange problem. Any ideas?

[dbsoundman]

Originally Posted by tiptop07

Yeahh, I have been going crazy tracking everything down. The only this I can have surmised this far is that the starter relay is on the pax side, and jumping that relay hasn’t helped, I’ve gone as far as jumping everything I can think of, and none of it seems to allow the bus to start. When I jump the solenoid it starts right up.. strange problem. Any ideas?

Which solenoid are you jumping to start it? I assume this is without using the key to start at all?

[tiptop07]

Yeah I am using the the starter solenoid, was really just doing it to make sure it wasn’t a start issue, but I am now pretty sure it’s the interlock.. I just can find the wire I need to ground it or close the loop. It’s wild