A strange thing has started on my 2004 Tacoma. The cruise control works fine when the headlights are off. As soon as I turn the headlight switch from off to either the parking light or full on position, the cruise control cancels. The green dash light stays on, but it acts like I hit the brakes. Also if I have the headlights on and then decide to try and turn the cruise on , the green dash light comes on, but it will never allow the cruise to actually set. No electrical work has been done on the truck at all. Any ideas? I looked at the electrical diagram and I don't see an common wire or anything that could be the culprit.

 

Is the cruise control also on the headlight switch/multi-function switch? You'll have to forgive me, I'm not overly familiar with the late model Tacos.

If it's all inclusive, probably a defective unit.

 

New to the forum here with '94 T4R 2wd auto with the same problem. Taking into my mechanic to check the head gasket repair (previous owner used water instead of coolant!) tomorrow and will ask him and relay any info. Meanwhile I've seen this thread had over 100 views but no answers, any help, anybody?

 

Yes the cruise control switch is on the steering wheel on the 2000.

Not the combination switch.

I would look at the tail light sockets a poor ground could try and ground back through the brake light circuit.

The Cruise computer sees that as the brakes being applied!!

 

Wyoming9 thanks for the reply, I installed new tail lights (from Rock Auto) and they are sealed all-in-one units so not sure why the ground would be bad. Basically plug-n-play so to speak! Any other likely culprits you can think of? My mechanic had no idea as to the cause and over inflated the estimate, claiming could take 5-6 hours to determine the fault. Not willing to spend that kind of labor charges on a mystery problem. Thanks for your help!

 

There is another thread with the same issue.

When did this start?

When the tail lights were installed?

These after market lights had the tail light and brake light and turn signal separate and plug into the Toyota Harness.



Does this have a converter box for a trailer plug??

Sometimes they short out.

Someplace the light circuit is feeding into the brake circuit .

Have you had someone watch the lights to see if the brake lights come on.

When Head lights are turned on.

Unless you have physical damage to the harness which should be easy to see

 

Wyoming9, thanks for the guidance, turns out the replacement tail lights had the brake lights on instead of running lights, including center high mounted one coming on! Since I hadn't been driving much at night anyway, never noticed because I didn't get pulled over for it and didn't have anyone I know following me either. Installed the lights over 4 months ago so return was out of the question. Cut and switched the wires to the brake light/running light and good to go!

Works like a champ now, hope this helps Buckeye.

 

I have the exact same problem on my 04 tacoma witlh headlights shuting off the cruise , also my brake lights are very dim when headlight are on all work great when headlights are off any ideas Found my trouble it was in the wiring for my trailer hookup i removed the wires from my talillights and all is working fine

 

Most likely your tail light sockets or bulbs are corroded .

Thus the tail lights are trying to ground through the brake light circuit which causes the cruise to see the brakes being applied so it will not engage .

physical damage to wires.

trailer converter box is also a possible place for problems.