# Replace Transmission Control Module Required Before Transmission Warranty?



## drake699 (Sep 6, 2018)

Hey All,

Long time lurker. I own a 2014 Chevrolet Cruze Diesel north of border. I've noticed the car a little sluggish in the past month. Last week, I had a roadside issue where the car wouldn't shift gears (high revving). I got it towed home.

Looked under the vehicle and noticed on the plastic cover there was a lot of transmission fluid that was leaking. I'm guessing the cover was catching the fluid so I didn't notice on the driveway. Also checked the engine light and got P0732: Gear 2 Incorrect Ratio.

I did the transmission fluid change, and only 1QT came out, so it seems to have been leaking for some time. Despite the fluid change the car still had issues going in and coming out of second gear. Took the car to the dealer.

The car has 103k km (64k miles) and is 4 years old. Was told the leak would be covered, and was coming from the axle seal. However, the service tech advised me they spoke to the warranty department and before they can consider it an internal transmission issue they need to replace the Transmission Control Module which is not covered under the 5 year warranty and costs $1500 (~$1100 USD). The service tech then advised if the TCM does not fix the issue then it can be considered an internal transmission issue and will be replaced under warranty. I was told if it comes to this I would still be out the cost to replace the TCM.

Does this sound correct? I have no experience dealing with manufacturer warranties this is the first new car I've owned. I have no problem paying for the TCM if that actually is the issue, but I feel if it doesn't fix the issue it should be reimbursed/covered under the transmission warranty as the replacement was done despite not being the issue.

Would this likely resolve the issue? Would the leaking fluid have damaged the TCM? or could the leaking fluid be a sign of obvious internal transmission issues?

Any advice?

TLDR: Car is laggy, not shifting properly, GM states TCM has to be replaced out of pocket before they can consider it an internal transmission issue and replace under warranty


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## Taxman (Aug 10, 2017)

_Before we can be sure the problem is the obvious and huge loss of fluid, you have to pay us to replace a computer which isn't leaking fluid. 
_
Does that accurately summarize what they said?
(shaking my head)

In USA, I'd call the District Service Manager at GM and ask him if he really wants me to sue him. 
Hopefully somebody else can suggest what to do in Canada.


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## Rivergoer (Mar 30, 2017)

Not sure if your leak is similar to mine but I brought mine in after noticing fluid dripping onto the topside of the belly pan and onto the ground occasionally. I did not have any shifting problems, just brought it in for the leak.

My leak (which occurred 11/30/17 @ 78,000 miles) turned out to be the seal between the transmission case halves. 

According to GM, because the Aisin transmission is ‘not serviceable’ the entire transmission was replaced new, free of charge, under PT warranty.

I was not required to pay for a new TCM first, they simply did the work, no questions asked.


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## Tomko (Jun 1, 2013)

Within the first six months of my CTD’s operational life I had the wont shift above second gear issue. TAC was contacted and they instructed the replacement of the TCM. This cleared the problem up - and it’s never recurred since. 

Of course this happened very very early in the warranty period and was covered at no charge to me. 

What I also discovered, back in the day, was that I could force a reboot of the original TCM and it would clear the problem up for the next ignition cycle, using the following procedure:

1) Stop car. Place in park. Turn off ignition. 

2) Remove key. 

3) Open driver’s door. 

4) Close driver’s door. 

5) Insert key and initiate engine start-up. 

6) Place transmission in Drive and proceed as per usual.


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## oreo382 (Sep 17, 2014)

Hold on there.In Canada the TCM is considered a major emission component and is covered for 8 years/80,000 miles.Look it up in your manual.The dealership you dealt with are either incompetent or are pulling something over on you.


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## drake699 (Sep 6, 2018)

Taxman said:


> _Before we can be sure the problem is the obvious and huge loss of fluid, you have to pay us to replace a computer which isn't leaking fluid.
> _
> Does that accurately summarize what they said?
> (shaking my head)
> ...


That's essentially what they said. My argument was with so much fluid that leaked out, I'm sure the damage is more to the transmission itself rather than the TCM and as such didn't feel justified paying the $1500 without knowing for sure that was the issue.

In the end their defense was that GM head office directly told them 80% of the time the issue is the TCM so before they won't approve a transmission change until the TCM is replaced which is not covered by the powertrain warranty.


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## drake699 (Sep 6, 2018)

Rivergoer said:


> Not sure if your leak is similar to mine but I brought mine in after noticing fluid dripping onto the topside of the belly pan and onto the ground occasionally. I did not have any shifting problems, just brought it in for the leak.
> 
> My leak (which occurred 11/30/17 @ 78,000 miles) turned out to be the seal between the transmission case halves.
> 
> ...


When I had the issue, I jacked it up and I was almost certain the leak was coming from the exact same spot; the seal between transmission case halves. I tightening the bolts hoping to squeeze the seal more and stop the leak. At the dealership, they advised me there is no leak from the centre seal and stated it was coming from the axle seal and dripping to that centre seal. 

I mean this might be the case, but I was so certain it was from that centre seal.


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## drake699 (Sep 6, 2018)

Tomko said:


> Within the first six months of my CTD’s operational life I had the wont shift above second gear issue. TAC was contacted and they instructed the replacement of the TCM. This cleared the problem up - and it’s never recurred since.
> 
> Of course this happened very very early in the warranty period and was covered at no charge to me.
> 
> ...


I didn't follow that procedure exactly, but I did notice when turning the car off and starting her up later, it started off just fine. However, within minutes it started acting up around 2nd gear.


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## drake699 (Sep 6, 2018)

oreo382 said:


> Hold on there.In Canada the TCM is considered a major emission component and is covered for 8 years/80,000 miles.Look it up in your manual.The dealership you dealt with are either incompetent or are pulling something over on you.


You my friend are a lifesaver.

I read this in bed last night, and immediately jumped out of bed and grabbed the manual and started going through it. I see it TCM 8 years/130,000km. 

With my manual I marched back to the dealership and showed the service consultant. They tried to pull a fast one saying that at the beginning of that "Emission Control Warranty" section it says passenger gasoline vehicles and diesel trucks but no mention of passenger diesel vehicles. It also says something along the lines of must fail provincial emission test (this has never been done as it's not required here before 5 years), but I argued that if they were to run it through the emission test it would fail because the MIL was on (instant fail) with the gear 2 code.

The consultant told me to take a seat and they'd consult a manager. I could see him go to the manager, and then about 4 other techs/consultants circled around passing around the manual. It took them close to an hour as they had to "call GM"; but the consultant came back and told me I was right, the TCM is covered under the Emission warranty and they will start the repair tomorrow. 

To be honest, I should probably start going to another dealership. Funny thing is the only reason we've been going to this one was because on our very first oil change I called around to see if any dealership had a filter in stock for the cruze diesel and this dealership was the only one in the city that said they did. Turns out they were wrong and didn't actually have the right filter. This should have been a red flag.

In any case, thank you all again!! Saved myself $1500+taxes. 

Will keep you guys posted if this actually fixes the issue.


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## Taxman (Aug 10, 2017)

Oh, well, a new TCM won't hurt anything, and yours was about to go out of warranty soon. 

But there's a 0% chance of fixing an output shaft seal leak by replacing the TCM, so they're still going to have to swap transmissions to fix the leak if GM's policy is to replace not repair transmissions.

Shouldn't their troubleshooting tree start with 'check fluid level and correct'? Then they'd never get to the TCM before fixing the fluid leak.


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## oreo382 (Sep 17, 2014)

drake699 said:


> You my friend are a lifesaver.
> 
> I read this in bed last night, and immediately jumped out of bed and grabbed the manual and started going through it. I see it TCM 8 years/130,000km.
> 
> ...


Glad I could help,I hate hearing about dealerships trying to screw people over."no mention of diesel vehicles"---after that comment I would get the repairs needed(for free) and say sayonara to that dealership forever.


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## ChevyGuy (Dec 13, 2014)

Can someone remind me where the TCM is located? I thought it was internal to the transmission - or am I confusing it with something else?

I suspect the root of this difficulty is "troubleshooting by code". The low transmission fluid caused excessive slippage which (properly) triggered the code. (There was a mismatch between engine speed, gear selected, and output shaft speed.) But some "book tech" is just looking at the code in his book and it's saying that in most cases, that code is caused by a TCM going south. (Which could well be, but given the low fluid, is not the most likely cause _in this case_.)


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## oreo382 (Sep 17, 2014)

ChevyGuy said:


> Can someone remind me where the TCM is located? I thought it was internal to the transmission - or am I confusing it with something else?
> 
> I suspect the root of this difficulty is "troubleshooting by code". The low transmission fluid caused excessive slippage which (properly) triggered the code. (There was a mismatch between engine speed, gear, and output shaft speed.) But some "book tech" is just looking at the code in his book and it's saying that in most cases, that code is caused by a TCM going south. (Which could well be, but given the low fluid, is not the most likely cause _in this case_.)


The TCM is external,on top of the trans,you have to remove the battery tray to get at it.


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## drake699 (Sep 6, 2018)

So just to update, I got the TCM replaced under warranty. Was called by service tech advising me issue is still there after replacement and they're looking into it. They eventually called me back advising me they're convinced it's the transmission itself; however, apparently these transmissions are on back-order across north america and they'd give me a call once they get one.

That was 3 weeks ago and still waiting. 

I've been racking up the mileage on the Malibu rental; the 1.6L engine does get some good mpg but not like the diesel.


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