2018 C300 won't go into D1, keeps going to N
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c300
2018 C300 won't go into D1, keeps going to N
Hi all.
Just bought this C300, 2018 model base. After a long drive (20 min or so), if I stop and try to park it won't go to D1, it keeps going to N, and then If I keep retrying it jerks and goes to D3 right away.
The fault code is P073E, which just means won't engage Reverse, which it also doesnt engage. Anyways figured out that the issue is the sensor on the TCM called SMP132 is faulty, and can't handle the pressure or heat or something, the silicon is just badly designed, so once the transmission oil heats up it starts misbehaving.
So I got that part which is on the TCM and the bad one needs to be soldered off (might have to dremel it off with a tiny drill, to save the connector wires on the TCM board)
The question is which solder to use the leaded or non-leaded? Leaded is more vibration resistant, and won't melts below 360F. The lead free one is higher melt temp of like 420+, but it's pretty brittle on the vibrations front.
They also say that leaded is good for heat tolerance, meaning on and off heat it behaves very well, like it won't crack or anything.
Anyways any advice would be good. Can I DIY trans oil change? I think I need some bleeder software?
Here is a video outlining the problem (swtich subs to English)
Just bought this C300, 2018 model base. After a long drive (20 min or so), if I stop and try to park it won't go to D1, it keeps going to N, and then If I keep retrying it jerks and goes to D3 right away.
The fault code is P073E, which just means won't engage Reverse, which it also doesnt engage. Anyways figured out that the issue is the sensor on the TCM called SMP132 is faulty, and can't handle the pressure or heat or something, the silicon is just badly designed, so once the transmission oil heats up it starts misbehaving.
So I got that part which is on the TCM and the bad one needs to be soldered off (might have to dremel it off with a tiny drill, to save the connector wires on the TCM board)
The question is which solder to use the leaded or non-leaded? Leaded is more vibration resistant, and won't melts below 360F. The lead free one is higher melt temp of like 420+, but it's pretty brittle on the vibrations front.
They also say that leaded is good for heat tolerance, meaning on and off heat it behaves very well, like it won't crack or anything.
Anyways any advice would be good. Can I DIY trans oil change? I think I need some bleeder software?
Here is a video outlining the problem (swtich subs to English)
