What you explain appears like the ported vacuum switch (Notice: this switch is only on 1999 and up cars). I’m undecided around the “hearing one thing jogging†— what does it seem like?
How concerning the encoder motor connector? I might suspect the latter, a) since it is much more vulnerable to corrosion due to road salt, etcetera. and b) because you reported the motor kicked in when rapping around the TC using a rubber mallet — that in all probability caused shock during the connector/wiring, more than enough to interact the motor.
Male, if it’s just a button assembly, don’t worry — there won't be any electronics inside the button assembly — They may be just that — buttons (switches). Meaning, it shouldn’t cost all of that A lot. The costliest part would be the dealers labour rate.
Some how the process thinks the 4Lo button is staying pressed, Which’s what you must come across. Sad to say, intermittent challenges are the hardest to seek out.
Properly, do what you'll be able to and allow me to know — And that i’ll do my best to assist you as a result of it — I’d prefer to see you repair it far too! Regards;
If I had to guess — both your encoder motor is shot, or lousy wires over the TCCM. In case you’re really into it, I’ll write-up the schematics to the wiring of the technique — this will allow you to trace and check factors together the procedure to pinpoint the issue. (I really need to scan them, so it is probably not today!)
I checked the wiring harness behing the passenger kick plate and it is okay As well as in tact. The wires are all building Speak to.
What I might do is take a look at the button assembly wires for the TCCM. If I’m not mistaken, I believe that the buttons are pulled substantial (+5VDC) and ground out on urgent them (I may very well be Erroneous, so you should double check!). So, I’d exam Each individual one of several button assembly wires in the TCCM. The ought to all be the same with no buttons pressed.
Hopefully, this tends to established you off in the correct more direction. Be sure to let me know what you discover as it could be of use to someone else here Sooner or later.
As I have mentioned often times in the three pages of the article… everything that I understand about the Chevy 4WD procedure has actually been posted right here. I haven't any additional info to offer. I am NOT a mechanic.
May be a TCCM difficulty, encoder motor challenge or possibly a transfer scenario challenge — all of which has been included inside this thread.
I listen to the TCCM click on when I engage and disengage. I also listen to what looks like air leaking if the drivers door is open and 4wd is engaged.
Your concern concerning the speed Management sensor — This might result in a problem, but I suppose it depends upon if it’s a transmission pace Regulate sensor, or a car pace control sensor.
Really, it appears like the process is examining the neutral switch and can only actuate in neutral. 4Lo is supposed to work this way, but 4Hi should really turn on the fly.