Truck stuck in 4 Lo

I may be wrong, but I think the OP is going off what the truck is indicating.

The truck is indicating it is in 4L, but as he did not do that intentionally, he knows their is an issue, but neither he, not dealer can say for sure what is caused the initial malfunction, and what is preventing a shift back to 4H or 2H.

So lots of potential causes. I am taking OP at his word explaining how it happened.

Possible:
1. Truck thinks it's in 4L but is not, so systems are preventing normal function and shifting.
2. Truck is in truly in 4L but was not set there mechanically, so something caused a shift electronically and continues to prevent shift to 4H or 2H.

 

Number 2 is exactly correct

 

Then by my thinking....the dealer wants $900 to perform the step in the diagnostic that is required to verify the transmission has suffered real mechanical damage. Seems like this should be covered under warranty.

2. If there is no mechanical damage to the transmission, then this step is not helpful to determine the electrical issue that caused the malfunction.

3. If there is mechanical damage caused as a consequence of the faulty electrical switch, actuator etc then it is still covered under warranty.

Am I missing something? What possible excuse can the dealer use to deny coverage?

 

I am not sure, but there is no doubt they will try to pin it on anything they can

 

I understand, but at this point the dealership has two strikes.

1. Ruined transfer case = $7000 with no proof, no diagnostic, no leg to stand on. So I would want to know if this was tech negligence/stupidity, or service advisor intent / fraud.

2. Diagnostic fee while in warranty. Once again, the recommendation from the dealer is not helpful in determining the cause of the malfunction, but the extent of damage. Not permitted under new vehicle warranty.

3. Seems like the correct first step is determining when/how the 4L came to be engaged, and how why it cannot be disengaged.

It makes sense to me that before they crack open or replace the transfer case, that they check the actuator, switch, relays, fuses for every component involved in the function. Otherwise this can happen again to the new case.

 

good god they want $7k to replace the transfer case?? You can get a used one for a few hundred and do that swap in a couple hours. I thought my dealership was crazy charging $3k for a clutch job but at least that's actually labor intensive

 

And if this is true, then an electrical issue seems even more likely. Hell even a dash switch failure seems significantly plausible. (Service manual even has a section for just dash switch troubleshooting.)

 

I'm actually thinking that there is a good chance that the problem is actually between the 2-4-L switch and the 4wd ECU under the dash.
Any beeping? Is the 4x4 or 4L light BLINKING ever (such as when it is switched to 4H or 2)?

Example: When the switch was in 2, and transfer case in 4L... if the 4L light was on solid (not blinking), then that proves that there is a problem between the switch and ECU.

 

Would think dealers would be able see all the service visits for any given VIN, no?

 

Yeah it seems very plausible.
And would explain why the truck was trying to go into 4Lo as soon as he started...
That said, The electrical design of the switch would make inadvertent 4Lo less likely and 4Hi more likely, but I have no idea of the mechanical design of the switch inside.

The switch electrical status is visible thru techstream, besides physically testing it, and the service manual procedure for testing it...

 

I don't necessarily mean that the switch itself is bad. Although that could be conceivable, just depends on the mechanical design (you can see that @BigWhiteTRD posted the schematics of it above), and it may also depend on how it handles undefined states, such as NEITHER 2-4 nor 4L being pulled low. Its also possible that the 4wd ECU itself has failed, in which case the state of the switch may be misreported, misinterpreted, or mishandled.

The danger from things like "techstream" is that if it reports that sensor X or switch Y is doing something unexpected, it may not actually mean that. It could also mean that the component that READS sensor X or switch Y has failed, or that a wire between them has failed. In other words, IF techstream reported (in this case) that the switch was set to 4L, then the next step would be to test the switch and the wires with a multimeter. If they check out with a multimeter, then probably the ECU has failed.

 

@riverrat12

Just curious if there is an update???????

FYI....I was off roading and my transfer case would not come out of 4-High. A dealership ended up pulling the transfer case apart and replacing internal parts. All covered by the warranty.

https://www.tacomaworld.com/threads...swers-please-help.585857/page-2#post-19529426

 

Update: As of right now everything is still the same. Toyota Corporate was suppose to call us back with information 3 different times this past weekend because they supposedly "red flagged" this case, which they never did... Today I have someone going out to inspect what they have actually done, which should be interesting. Should know more about it by end of the day

 

UPDATE: So I just got the call from Toyota and they are replacing my actuator under the warranty! I don't know why all of the sudden they changed their minds and went from accusing me of the damage based off the way my truck looks to now no questions asked they are fixing it and covering it. Especially since from the beginning they told me I needed a new transfer case, when it was really just the actuator I guess... Regardless I am stoked. Maybe constantly calling corporate and opening cases with them worked.

Thanks everyone for the advice.

 

Uh, they actually had the dealer take a real look at it?

 

yep

 

Hope it fixes it...

 

That's really good man. Everybody like happy endings

 

Esp the Patriots! Hahaha!