Car decides on "C" mode?!
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2019 G70 6MT & 2022 Ford Maverick XL
Car decides on "C" mode?!
I know I'm not crazy. This has been happening to my car lately and I've been brushing it off as "I must've done that on accident" but not anymore, too many offenses.
I will look in the gauges and find my car is in "C" mode rather than "S", even though I have always driven in "S" and never press the button. It's happened probably a dozen times lately. I press the button and put it back in "S" mode until sometime later I notice it is again in "C". WTF!
Has this happened to anyone before? Any ideas?
Edit: Car runs fine, shifts fine, has no stored codes, and is @ 67,400 miles.
I will look in the gauges and find my car is in "C" mode rather than "S", even though I have always driven in "S" and never press the button. It's happened probably a dozen times lately. I press the button and put it back in "S" mode until sometime later I notice it is again in "C". WTF!
Has this happened to anyone before? Any ideas?
Edit: Car runs fine, shifts fine, has no stored codes, and is @ 67,400 miles.
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2019 G70 6MT & 2022 Ford Maverick XL
Interesting.. I hope it stops having such frequent episodes. It's not a big deal as I typically don't notice it driving any differently, I just didn't want it to be a sign of something to come. I never have a problem with the BMW's transmission.. oh wait, it's a 6-speed manual. I kick myself for not going 6MT in the C230. 
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Matt - just check that it's not the dreaded TCU plug leaking O ring in the front of the 722.6 gearbox. I've just bought a spare for mine expecting it to let go one day. I hope with a $8.50 spare lying around it won't happen. I'm coming up for my 60,000Km transmission oil flush & change.
Last edited by Glyn M Ruck; Dec 2, 2009 at 05:21 AM.
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2019 G70 6MT & 2022 Ford Maverick XL
It says on work order "replaced with updated parts"..
Hrm. I'm not mechanically inclined enough to check this myself. I will say that when the car had the problem, it never did the "C" thing.
Hrm. I'm not mechanically inclined enough to check this myself. I will say that when the car had the problem, it never did the "C" thing.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Just stick your head under the car on the passenger side & see if the plug is wet - front diagonal of tranny. If you previously had this problem we don't know how well they dried out the TCU harness. Check passenger footwell footplate area where the TCU is mounted for oil.
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Glyn, other than the TCU plug issue, is it possible the switch has an intermittent short, that causes the TCU to switch modes?
I had the hood switch intermittently short causing the "hood open" message on the MFD a dozen or so times since my car was new. Hasn't done it in quite a while, though.
I had the hood switch intermittently short causing the "hood open" message on the MFD a dozen or so times since my car was new. Hasn't done it in quite a while, though.
Last edited by johnand; Dec 2, 2009 at 10:42 AM.
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From: Saint Augustine, FL
1999 CLK320 (sold), 2007 C230 SS (gone), 2000 Grand Marquis, 2011 CR-Z, stay tuned...
I want to say that I have noticed this a couple times too. Not enough to make an impression, but something that I do remember. It hasn't happened in soooo long though.
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2019 G70 6MT & 2022 Ford Maverick XL
Meh, I would love for my C230 to be a 6MT.. but then it would be a non-weak sauce transmission in a generally weak sauce car. My 135i is a 6MT and I wouldn't have IT any other way. Twin turbo FTW!
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From: Houston
2007 C230 Sport
What a weird problem... And I thought my famous hvac system turning it's self was odd at first!!
Manual transmissions are by far the best, but I agree - in a 200hp benz, not totally necessary!
Manual transmissions are by far the best, but I agree - in a 200hp benz, not totally necessary!
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2019 G70 6MT & 2022 Ford Maverick XL
