tn 55 no dash lights,no charge

[joe d]

problem here will start and run , it will not charge and has no dash functions, checked it all ,yes battery is charged up ,fuses are good, removed altinator had it checked its fine, seems all relays are ok also wires from altinator are in fine shape by testing,,, the only thing i cant test is the dash on this model is the dash the brain center, no it does not have a module or shuttle shift. at a real loss here,i only need to find 12 volts to the red wire at the altinator (16 ga)

 

[jinman]

Joe, I know you said the fuses were good, but I want to make sure you used an ohmeter to check them (most likely fuse #4 or #5). I just think everything you are describing sounds like a fuse problem, and I know they can sometimes be very hard to see if they are blown. An ohmeter will tell you for sure.

Excitation for the alternator comes in on the brown wire to terminal "L". That same fuse powers the alternator light in the instrument panel. Therefore, if the alternator light is not ON, then it's a good sign the fuse is blown. If the light is illuminated, then the fuse is okay. There is also an isolation diode inline with the lamp. I'm not sure where your diode pack is located.

 

[joe d]

ok rechecked all fuse and again all are good ,now on the altinator the little red wire (exciter) if i sock 12 volts to it i get the no charge light on the dash so i know my wire is good ,,,,now all hooked up and i turn the ignition switch to the on position i get no bulb checks on the dash no nuttin no lights no gauges work.. but if i start and run and excite that wire on the altinator it charges and my dash lite (red no charge lite )is on but its charging ,,,, also removed all dash bulbs and checked them ,,, all grounds are also intact and are good,,, again is the dash a module and part of the smart system

 

[joe d]

ok now doin some heavy pokin all leadin up to the dash module the 15 pin plug on the back has created movemet by back probe the ground and red wire........ now i have a temp gauge a tick tock wih my head lights on and a fuel gauge thats pegged
thinkin we headed down the road of a ground prob but still not sure wher the heck its at but all input is welcome

 

[joe d]

ok some exciting news but expensive removed the dash (module) put on bench and removed the 6 tiny nuts and seperated the cluster !! waaaaallllaaaa its a printed circute in there and to no ones suprise one of the tiny soldered ribbons fell out looked like a a hunk a hair so now just ordered it and 271 bucks mite be able have all working ,,,,,

 

[jinman]

Joe, the red wire is your main power out of the alternator and should go over to the starter and then up to the main 40 amp fuse in the holder right above the starter. The brown wire to the alternator is the excitation wire. The orange wire is probably coming from Fuse #1 and is the voltage regulator sensing wire. When you turn on your key, you should feel 12v at that orange wire. For the brown wire: before you start your engine, power from fuse 4 or 5 goes positive to negative across the isolation diode, thru the alternator light and back to the alternator on the brown wire and to ground. When the alternator starts putting out power, the brown wire goes positive and therefore the potential across the light and the diode are the same from the fuse or the alternator, so the alternator light extinguishes. If you are not getting an alternator light on with the key on and the engine not running, something is wrong. It could be that the diode has opened.

The final wire off your alternator is pink. It is the tach input pulse stream to the tachometer in the instrument panel and is on a separate plug in the back of the alternator.

Here's a photo of your connections on the alternator showing the colors of wires and where they should be in case the wire colors have faded.

 

[joe d]

jim,,,,,,,,,, the alt. i have a denso if you was to look at mine from behind as yours youre pink is where my 16 ga red is your brown is where my hot (batt) is and where your red (batt ) is i have a black (grd).............but with what i found inside the module itself i will lay money that little ribbon of solder is causing the problem ............... this thing easly comes apart and if ya look close ya kin see has some keeerosion in spots of the ribbon solder mite be they sould had clear coat it ,,,, i am going to do a little testin with a stran a copper wire and paste it in what do i have to loose

 

[jinman]

Joe, I apologize for leading you down the wrong path with info on a 40 amp alternator.:ashamed: I'm sure yours works similarly, but the wire colors and functions are certain to be different. Somehow, I read your "tn 55" as "TC 55" and just went off the deep end. It sounds like you have a handle on things despite my trying to lead you astray. I'll tuck my tail between my legs now and go sit in the corner. . .

 

[joe d]

nope dont worry about it they all do same thing similar, yep mine is also a 40 amp,,,, i tell ya all this fancy crap well bein for the last hundred years ya could leave a tractor outside and not worry in the rain in the snow and now seems if ya aint got a heated geerage where this sissey thing kin rest it aint werth a dime ,,the older tractors and cars still run more dependable and cheaper than this new fangled hi tech stuff shipped over from who knows where.. wait till ya work on a new freightliner with the multiplex etetrical system and its smart switches ,,,,, so not to worry but i hope i did shed some light on a no charge and no dash lights but a start and run,,,,,the sun will be up in the mornnin........thnaks again im sure i will be back