Team-BHP - TCU failure in my Maruti Baleno CVT

I am now in a serious show-stopping situation with my Maruti Baleno Delta CVT model.
It's a 2018 model with approx 28K on the ODO. Single-handed.

2 days back when I started to drive my car from my parking, I was unable to move. When I called my FNG mechanic, he said there is an issue with the gearbox. He recommended I take the car to the nearby ASS since he doesn't have experience dealing with the CVT gearbox which I felt was very genuine and appreciable.

Now the car is with the ASS and they are saying that it is TCU failure. They are asking me to replace the TCU completely for which they are quoting me around 60K.

I wrote to Maruti and now everyone (OEM, Dealer and Customer (myself)) is on the discussion table. And still, they haven't diagnosed the cause of the TCU failure. In fact, I did ask for the error codes that they haven't shared/revealed yet. And they mentioned about 3 errors - range (DTE) sensor error, outside temperature error and TCU error.

In fact, they are pushing me to go for the TCU replacement. Now that the car is out of warranty period, the cost will be on me. And I don't think it is a good idea to claim insurance as well (since there is no external damage to the car).

What should be done?

Quote:

Originally Posted by Livnletcarsliv (Post 5134050)

Two days back when I started to drive my car from my parking, I was unable to move. Now the car is with the ASS and they are saying that it is TCU failure, for which they are quoting me around 60K.

This is weird. I just can't accept the argument on the TCU. I haven't heard of a Transmission Control Unit needing replacement unless, of course, the unit was exposed to high voltages OR water. Please recall of any incident or some work that was done just before this failure viz. one day it was working fine, but something happened and the next day it stopped working. The issue could be due to one or more of the following:

1. rodents clipping some wires
2. transmission running low on oil
3. wrong oil filled into the transmission (if the transmission oil was replaced sometime in the recent past)

Possibility #2 can be verified by removing the transmission oil dip stick and checking the oil level when cold.

I have heard of a Toyota Corolla with a torque converter AT not move and the transmission "fuming" due to low oil due to a leak. The moment the right grade oil was topped up, it was all fine.

Quote:

Originally Posted by vigsom (Post 5134061)

This is weird. I just can't accept the argument on the TCU. I haven't heard of a Transmission Control Unit needing replacement unless, of course, the unit was exposed to high voltages OR water.
1. rodents clipping some wires
2. transmission running low on oil
3. wrong oil filled into the transmission (if the transmission oil was replaced sometime in the recent past)

Yes, only the first one is a possibility. But, total TCU replacement due to a rodent bite is still the weirdest of the weird.
And why will Maruti still not identify this simple reason?

Quote:

Originally Posted by Livnletcarsliv (Post 5134050)

I am now in a serious show-stopping situation with my Maruti Baleno Delta CVT model.
It's a 2018 model with approx 28K on the ODO. Single-handed.

I hope your issue is resolved timely. I would also suggest to shoot an email to crm@maruti ( I don't remember the exact email id). Since it's a 2018 car and out of warranty, they're asking you to pay for replacement. May I ask why you didn't pick up extended warranty?

The DTC list will give us more clarity, but sensor fault for DTE(fuel level sensor), outside temperature, TCU fault can't occur all at once and how will replacing the TCU alone will solve other two? Because the TCU is not related to either of these sensors. Only probable connection might be a common power cable at fusebox and that too is rare.

So, better to check the wiring manual at ASS. Remove the TCU (if not integrated into transmission) and connect to a different vehicle if available in service center. If it works there, then TCU replacement idea can be trashed. If no vehicle is nearby, or TCU is integrated on transmission, then remove the TCU connector, check fuses, connect back and try doing battery terminal disconnect too. I hope battery is at good voltage level.

Quote:

Originally Posted by Livnletcarsliv (Post 5134068)

Yes, only the first one is a possibility. But, total TCU replacement due to a rodent bite is still the weirdest of the weird

Sometimes, the OBD scan shows an error description which leads people to suspect the unit mentioned in the description. Eg. look at the error code mentioned in this post - P2764 viz. Torque Convertor Clutch Circuit Low Voltage. When I saw this error code on my car, I did not suspect the clutch or the solenoids, but just traced the wiring from the Transmission Control Unit to inside the engine bay and found the culprit.

I still believe that your TCU is fine, and the problem lies somewhere else. It is a good idea to check the DTCs, then look up the service manual, and also check fuses/relays connected to the CVT to rule out all possible causes one by one; not sure if the Maruti Auth. service will take such pains, though.

This thread also serves as a reminder to all of us to take the maximum extended warranty coverage available :thumbs up. Today's cars have too many expensive electronic parts (as seen in this very thread) and even Maruti's bills can be exorbitant. 60 grand is a lot of money! Just take the 5 - 7 year warranty offered by the OEMs and sleep in peace.

Hope things work out for you, Livnletcarsliv :thumbs up.

Quote:

Originally Posted by Livnletcarsliv (Post 5134050)

It's a 2018 model with approx 28K on the ODO. Single-handed.

In fact, they are pushing me to go for the TCU replacement. Now that the car is out of warranty period, the cost will be on me. And I don't think it is a good idea to claim insurance as well (since there is no external damage to the car).

If Maruti doesn't approve warranty replacement and you are out of options I have a suggestion that could help solve the issue at a cheaper cost. I suggest you to take the damaged part from your Baleno, go to your car parts scrapyard and pick that part from there. You can replace it ans check if that works. If it solves the issue, then job done.

Since you would pick it from the scrapyard, bargain hard and get it as cheap as possible.

Quote:

Originally Posted by Goldenboy (Post 5135434)

Any reason why you don't want to claim insurance? Isn't this exactly the sort of thing you take insurance for?

Insurance is for accidental damage.

This kind of non-accidental failures are not covered, unless the OP has specifically included additional electronics & engine cover in his insurance.

Quote:

Originally Posted by abhishek46 (Post 5135551)

Insurance is for accidental damage.

This kind of non-accidental failures are not covered, unless the OP has specifically included additional electronics & engine cover in his insurance.

To further add on to what you've pointed out, Physical Damage Insurance coverage in policies cover losses caused by specific perils - fire, collision, rollover, vandalism, theft, falling objects, wind, earthquakes, flooding etc.

Mechanical failures aren't covered by insurance polices anywhere in the world. So not even coverage that was bought for engine protection would apply here; the engine protect cover applies during flooding.

Quote:

Originally Posted by Goldenboy (Post 5135434)

Any reason why you don't want to claim insurance? Isn't this exactly the sort of thing you take insurance for?

Insurance doesn’t cover this. The only saviour in this case would have been the extended warranty which OP promptly missed it.
Always opt for extended warranty those few thousands save more thousands in expenses like this. An important lesson to everyone.

After continuous discussions, questions, and follow-ups, the ASS did a thorough inspection of the car. The issue is wiring damage. And the culprit is no one but the SQUIRREL. They pulled out a lot of squirrel nests from inside the wiring sleeves, etc. My car will be ready in a couple of days.

Thank you all for all your valuable recommendations and advices.