Overdrive not working

[batfire]

Hello Tahoe Fam.
I have a 04 Tahoe, that had few problems. Windshield wipers not working on any setting speed, only all the way to fast speed. And also my overdrive not working. I replaced the turn signal switch (which includes OD and wiper switch) Did not fix the problem. I replace the module and a motor for the wipers and that fixed the problem. However my overdrive still not working. Can someone please help?

 

[MO Viet Vet]

Could have told you about the module problem. They were known for that. If you have a tow/haul mode for the trans make sure that is turned off. Check fluid level and if all that looks good then may be the range selector switch on side of trans, better known as neutral safety switch. Any CEL?

 

[remauto1187]

You sure 2nd is there? The 4L60E (TH700R4 formerly) has a band that is used for 2nd and 4th(OD) only. Count shifts while conservatively opening the throttle. Dont confuse Torque Convertor lockup with a shift.

 

[batfire]

Sorry friends, had a brainfart. Not the overdrive, is the cruise control that it's not working. Any suggestions?

 

[rockenthebowtie]

Check your high mount brake light

 

[batfire]

@rockenthebowtie The high mount brake light is working fine.

 

[rockenthebowtie]

Have you checked your fuse, in the ip fuse block 10amp cruise fuse, for the most part unless you have an actual open circuit to the turn signal multifunction switch or a history code pertaining to the tac module the only thing it can be it the turn signal multi function switch

 

[batfire]

I have not checked the fuse yet, I did however replaced the multifunction switch already.

 

[rockenthebowtie]

Would then need scan data to see if the brake switch for cruise control is closed or open with brake pedal NOT APPLIED it should read closed they have 2 circuits one for cruise control and for the brake lamp switch. I mean you can try that. Also make sure there are no history DTC for the TAC module because that will also keep it from engaging even though the ses light isnt on

 

[batfire]

Ok, I just got my truck back (mother in law using it) The high mount brake light was out and I just replaced it. Cruise control still not working.
I will check the fuse today