Cat handler problem

[Nitrams]

Have a 2002 Cat Th83 with a transmission problem caused by electrical problem. Struggling to fully get my head around what is causing the problem. Im fairly sure its the same wiring etc as Cat Th62,63,82. Anyone have or know anyone with intimate knowledge of the wiring surrounding the transmission controller (fwd/rev shuttle and gear selector lever)
The wiring between the controller and solenoids is fine but controller is not powering all the correct solenoids in certain gears.Have tested output at the T/C end to rule out loom issue between controller and solenoids. Have bought a new controller thinking i have id this as problem but the new one is exactly the same as old one. Its not powering rev soenoid in 2 rev gears and not powering solenoid 2 in any fwd gear. I can only guess its related to the input wires into T/C but dont have any understanding of what is what here.
Any help or contacts appreciated.
TIA

 

[Full of bull(s)]

Have a 2002 Cat Th83 with a transmission problem caused by electrical problem. Struggling to fully get my head around what is causing the problem. Im fairly sure its the same wiring etc as Cat Th62,63,82. Anyone have or know anyone with intimate knowledge of the wiring surrounding the transmission controller (fwd/rev shuttle and gear selector lever)
The wiring between the controller and solenoids is fine but controller is not powering all the correct solenoids in certain gears.Have tested output at the T/C end to rule out loom issue between controller and solenoids. Have bought a new controller thinking i have id this as problem but the new one is exactly the same as old one. Its not powering rev soenoid in 2 rev gears and not powering solenoid 2 in any fwd gear. I can only guess its related to the input wires into T/C but dont have any understanding of what is what here.
Any help or contacts appreciated.
TIA

You can buy manuals on eBay for these models. I bought a service manual I think that has electrical diagrams in it. I bought it to save time/money for my mechanic

 

[leone75]

search an old thread on here Cat TH62 drive issue I don't know how to link it

 

[icanshootwell]

Have a 2002 Cat Th83 with a transmission problem caused by electrical problem. Struggling to fully get my head around what is causing the problem. Im fairly sure its the same wiring etc as Cat Th62,63,82. Anyone have or know anyone with intimate knowledge of the wiring surrounding the transmission controller (fwd/rev shuttle and gear selector lever)
The wiring between the controller and solenoids is fine but controller is not powering all the correct solenoids in certain gears.Have tested output at the T/C end to rule out loom issue between controller and solenoids. Have bought a new controller thinking i have id this as problem but the new one is exactly the same as old one. Its not powering rev soenoid in 2 rev gears and not powering solenoid 2 in any fwd gear. I can only guess its related to the input wires into T/C but dont have any understanding of what is what here.
Any help or contacts appreciated.
TIA

I know when I lost 2nd gear on my 407, I thought it was the solenoid but it turned out to be the twist gear changer in the cab, easy to replace and didn't cost to much, around £280.

 

[Nitrams]

search an old thread on here Cat TH62 drive issue I don't know how to link it

Thanks, already had a good troll thru these tho

 

[Nitrams]

I know when I lost 2nd gear on my 407, I thought it was the solenoid but it turned out to be the twist gear changer in the cab, easy to replace and didn't cost to much, around £280.

Not bad at all, £1000 for this one

 

[ACEngineering]

I know when I lost 2nd gear on my 407, I thought it was the solenoid but it turned out to be the twist gear changer in the cab, easy to replace and didn't cost to much, around £280.

bargain, TH62 levers are over 1k now

 

[Nitrams]

You can buy manuals on eBay for these models. I bought a service manual I think that has electrical diagrams in it. I bought it to save time/money for my mechanic

Thanks, think ive found one, over 4000 pages long

 

[Nitrams]

Does anyone know what the transmission diode inside the cab does or how it presents itself if faulty?

 

[Sledgeit 1]

Have a twisty gear changer if you are looking for one.

 

[Nitrams]

Have a twisty gear changer if you are looking for one.

just bought one as above.

 

[cousinjack]

Have a 2002 Cat Th83 with a transmission problem caused by electrical problem. Struggling to fully get my head around what is causing the problem. Im fairly sure its the same wiring etc as Cat Th62,63,82. Anyone have or know anyone with intimate knowledge of the wiring surrounding the transmission controller (fwd/rev shuttle and gear selector lever)
The wiring between the controller and solenoids is fine but controller is not powering all the correct solenoids in certain gears.Have tested output at the T/C end to rule out loom issue between controller and solenoids. Have bought a new controller thinking i have id this as problem but the new one is exactly the same as old one. Its not powering rev soenoid in 2 rev gears and not powering solenoid 2 in any fwd gear. I can only guess its related to the input wires into T/C but dont have any understanding of what is what here.
Any help or contacts appreciated.
TIA

One day when our th62 was having issues, I sat down with the t/c and a multimeter and worked out which wire did what.
Unfortunately I didn’t write it down…

But I don’t remember it being much of a mystery …

maybe one or two wires carrying power in, then one wire each to power the fd, rev, 1st, 2nd and 4th gear solenoids..

3rd gear is activated when none of the other gear solenoids are powered up..

 

[cousinjack]

also from memory,
The wires are grouped into 3 ( ??) connectors ?

one is for fwd/rev and one for gear selection.

 

[cousinjack]

Does anyone know what the transmission diode inside the cab does or how it presents itself if faulty?

Never heard of it …..

but a diode allows power to flow in one direction only. Faults could be either allowing power to pass back through the diode. At a guess this would cause multiple solenoids to engage ,
Or more likely, go open circuit and not allow power to a solenoid ..

 

[Nitrams]

also from memory,
The wires are grouped into 3 ( ??) connectors ?

one is for fwd/rev and one for gear selection.

Yes 3 connectors, 2 supplying output voltage to solenoids and the other plug is inputting into T/C. This is what i dont fully understand. It has input from handbrake, neutral trans switch and maybe other stuff