code P1860

I have a 1998 jimmy 2 wheel drive with check engine soon light on and the code is P1860. I replaced the TCC solenoid and the wire harness and check the wires from computer to transmission and they check good, so I reset the computer and the light came back on again. I took it to a mechanic and he scanned the transmission and the solenoids are working fine. Now he's telling me it could be an electrical problem. Has anybody had the same problem? If so how was the problem fixed?

Did he use a trans scanner and command and cofirm tcc solenoid operation and proper lock up?

This is a code for the torque converter clutch circuit (PWM solenoid circuit.) Check the solenoid and see if it has continuity. The wires at the connector are tan/blk and brn. You may be able to pick up a problem with that solenoid that the computer can't see.

Also, is the converter actually locking up? Verify by lightly stepping on the brake (enough to trigger tcc disengage, but not enough to wake up the brakes) while maintaing speed and see if the revs jump a few hundred or so. I'm sure you've done this, but it couldn't hurt to recheck.

HTHs