Shift module only sending 5 volts to switch?


ecgreen

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Hey guys,

Still troubleshooting my electronic tansfer case. I went through the diagnostics in the Tech section (thank you whoever wrote that!). I passed all tests except the last one. It seems that my module is only sending 5 volts to the switch. The diag sheet says it should read 12 volts when you backprobe the module and turn the key on and press the 4x4 button. I am only getting 5 volts. Is this a thing or did I do something wrong? I am also not getting any voltage on the orange wire on the shift motor side of the transfer case connection. I am thinking a bad shift module. Thoughts? Hope I was clear enough.
 


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ecgreen

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Swapped in a new unit and no luck. Gonna go wire the motor to a switch.
 

Shran

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I would bet money that your shift motor is bad. I have run into this several times now and same deal... 5 volts, no shift. New shift motor fixed it both times. I suspect that there is some sort of resistance issue in the motor itself, hence the low voltage.
 

ecgreen

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I would bet money that your shift motor is bad. I have run into this several times now and same deal... 5 volts, no shift. New shift motor fixed it both times. I suspect that there is some sort of resistance issue in the motor itself, hence the low voltage.
Interesting, thanks for the post.
Did you have lights at the switch? I do not.
 

bobbywalter

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light at switch can burn out.


make sure the grounds at the cowl on both sides are good too. quick check is to jumper right from them to bat ground to see if that helps. though usually if that is the issue the oil psi is reading erratic as well.
 

ecgreen

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I put power to the switch, as per the directions in the tech article, and the lights work.
 

bobbywalter

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Did you ground the cowl ground directly.?.
 

Shran

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Interesting, thanks for the post.
Did you have lights at the switch? I do not.
Dash lights yes, indicator lights, kinda. There was part of the process that backprobed the lights themselves, they did light up there, but never if I just pushed the button. After replacing the shift motors, they worked as they should.
 


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