Ground locations?

Hello,

My 4 Lo is flashing and the selector knob doesn’t do do anything, as if it’s not getting any connection to it. The front actuator was soldered a couple of years ago so I’d like to assume it’s still good, as it’s always worked great since.

Also, my cruise control quit working and will randomly come on for a split second and accelerate the truck. Radio doesn’t irk and etc. Horn works and no air bag light.

I am going to replace the clock spring and see if that helps. I’ve seen it mentioned where the flashing 4 Lo was a symptom of a bad ground. I’m expecting all these things may be connected and there is a bad ground.

Is there a guide on ground locations? Someone had a ground fix on the passenger side that fixed their 4 Lo. Any particular ground spot there? Thanks!

 

The grounds for the 4wd limit switches and cruise switch are on the back of the passenger cylinder head (Ground Point EE), the 4wd ECU ground is behind the right kick panel.
https://www.tacomaworld.com/threads/4wd-system-operation-help-thread.742420/

 

Thank you Dm93! Great write up on the trouble shoot! So it sounds like I need to check the actuators vent lines, then check the ground and then check the 4wd switch pending conditions of each.

with the ground point, am I just looking for loose connection, corrosion etc? Should I just disconnect and clean up and apply some diometeric grease?
With the switch am I just using a multimeter to check the volts against the chart you provided? Do I do this with key switch off?
Thank you very much for your help!

 

Yes especially if you live in an area that they salt the roads corrosion on wiring and grounds is a very common occurrence.
It wouldn't hurt to clean and grease them all, make sure you give all the wires the tug test to make sure none are broken internally.

On testing the 4wd circuits all my tests were done key on-engine off with the voltmeter ground on body ground but you can use any known good ground.

 

Okay awesome. I’ll check the switch this eve. I did a quick glance at the EE ground. Looks like pretty good condition. I attached an image of what I think is it. Does that look correct? I’ll check over the diagrams some more and see if I can check other ground points. Thanks for the help.