Gearbox/transmission module fault

tacticalx86

tacticalx86

tacticalx86

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Bought a used BMW 320i automatic from a dealer end of May. I hit a pothole recently and the tyre on the driver's front nearside was funny so i took it in to a garage, expecting something like the wheel needing realigning or the shocks/suspension links having gone. (turns out the tyre was just over inflated). However in the course of diagnosis they told me the gearbox module/transmission module had an issue with it. They didn't appear to know much about it, and suggested i take it to a a garage which specialises in bmws. The thing is i've had absolutely zero issues with gear shifts and there's no warning light on the dash. Does anyone here know much about these modules? I'm under the impression that whilst the device doesn't cost that much itself, the gearbox would need to be rebuilt or replaced entirely which would obviously be phenonemally expensive. The car has until about august 25th on warranty but usually they want a quote first, and getting a diagnosis/investigation from a bmw garage (not an official one) will cost £60-£100. Just wondering if there is an issue, will it need to be replaced? I'm guessign eventually but I kept my last car for about 3 years with a broken synchro and it never got worse. Or could the obd message be an error, as there is no warning light on the dash? It was serviced and MOTed when I bought it and no faults.
 
How old is the car? Was it a local dealer (assuming so) or a BMW dealer?

Try get a code reader on it if you can, clear it and give it a day or so of driving. Might just be an erroneous code.
 
ShivP said:
How old is the car? Was it a local dealer (assuming so) or a BMW dealer?

Try get a code reader on it if you can, clear it and give it a day or so of driving. Might just be an erroneous code.
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12 years. Yes local dealer. Warrantywise warranty which doesn't seem worth the paper it's written on

Where can I get a code reader from?
 
tacticalx86 said:
Bought a used BMW 320i automatic from a dealer end of May. I hit a pothole recently and the tyre on the driver's front nearside was funny so i took it in to a garage, expecting something like the wheel needing realigning or the shocks/suspension links having gone. (turns out the tyre was just over inflated). However in the course of diagnosis they told me the gearbox module/transmission module had an issue with it. They didn't appear to know much about it, and suggested i take it to a a garage which specialises in bmws. The thing is i've had absolutely zero issues with gear shifts and there's no warning light on the dash. Does anyone here know much about these modules? I'm under the impression that whilst the device doesn't cost that much itself, the gearbox would need to be rebuilt or replaced entirely which would obviously be phenonemally expensive. The car has until about august 25th on warranty but usually they want a quote first, and getting a diagnosis/investigation from a bmw garage (not an official one) will cost £60-£100. Just wondering if there is an issue, will it need to be replaced? I'm guessign eventually but I kept my last car for about 3 years with a broken synchro and it never got worse. Or could the obd message be an error, as there is no warning light on the dash? It was serviced and MOTed when I bought it and no faults.
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I'd suggest they have probably plugged it in and seen some sort of historic fault code in the gearbox. If the gearbox is working fine, and there is no codes showing on the dash, I'd be inclined not to worry about it. When an auto gearbox is going wrong the first thing you're going to start getting is some harsh/rough/strange shifts, follows by some faults on dash.
 
I’m guessing here , but it will probably have a ZF box which the vehicle manufacturers will tell you are sealed for life and do not need any servicing. This is wrong.
If the shifting pattern is all to **** then it definitely needs a service, but for now get a code reader and keep an eye on it.
 
Ok so I've noticed two times in the last few weeks including tonight my car has had issues slowing down. This is where I start breaking and brake but the car continues to shift forward. Tonight it was at a set of red lights, thankfully no other cars around. Can a bad TCM cause this? The brakepads both front and back were replaced recently.
 
A transmission control module implies it's an electronic component, in which case it would just be its replacement and not a gearbox rebuild. Obviously if this module is faulty it could be causing unusual behaviour in the gearbox.
 
radderfire said:
A transmission control module implies it's an electronic component, in which case it would just be its replacement and not a gearbox rebuild. Obviously if this module is faulty it could be causing unusual behaviour in the gearbox.
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The garage I went to (not a BMW specialist just the one which found the error code) suggested it would be?
 
tacticalx86 said:
Didn't know that was a thing! Thanks might consider it, could well need a fluid change i suppose
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It depends on the car and the gearbox used. When I was looking at purchasing a Skoda, the lower end autos had a "gearbox for life" so nothing needed doing unless it went faulty. On the higher end models, VRS spec etc then it was a 40k recommendation (and some year time) to change the oil in the gearbox.

A quick Google search of your car and model details should find if it needs doing or not.
 
Nemiyen said:
It depends on the car and the gearbox used. When I was looking at purchasing a Skoda, the lower end autos had a "gearbox for life" so nothing needed doing unless it went faulty. On the higher end models, VRS spec etc then it was a 40k recommendation (and some year time) to change the oil in the gearbox.

A quick Google search of your car and model details should find if it needs doing or not.
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it's an automatic gearbox
 
Alright so I think I definitely have an issue and its actually dangerous.

First time was a couple weeks ago, braked approaching traffic light turning to amber/red, and the car just wouldnt stop. it was still going about 1mph even with the brakes flat to the floor.
Second time last night, another st of traffic lights, same thing.
Took the car to a garage this morning, they found no issue whatsoever with the brakes or brakepads.
 
tacticalx86 said:
Alright so I think I definitely have an issue and its actually dangerous.

First time was a couple weeks ago, braked approaching traffic light turning to amber/red, and the car just wouldnt stop. it was still going about 1mph even with the brakes flat to the floor.
Second time last night, another st of traffic lights, same thing.
Took the car to a garage this morning, they found no issue whatsoever with the brakes or brakepads.
Click to expand...

Then this is nothing to do with your gearbox. If your car continues to move forward despite you having full pressure on the brakes - it is your brakes at fault. Your brakes are *easily* able to win the battle between your engine/gearbox wanting to go forward and your brakes trying to stop you.

When you said your brakes are "flat to the floor" I'm assuming that was just a turn of phrase, and your brake pedal feels firm, consistent and with no dead spots at the top of the pedal?
 
Also can be related to a switch that regulates the gearbox pressure.
On most cars, when the brake is pressed, the gearbox disengages the gear at stop so there is no "pressure" from the transmission onto the brakes.
 
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