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Steve, BMW Expert
Category: BMW
Satisfied Customers: 25413
Experience:  BMW Expert
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The auto transmission light on my 525i came on recently

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Hi, the auto transmission light on my 525i came on recently and feels a little sluggish pulling away in 1st but then drives fine once I'm going. I had a mobile mechanic out to put it on a diagnostic computer which showed codes: P0743, P0700, P0078, P0748 and P0705. The mechanic told me the car seems is saying its in 4th gear when it's supposed to be in neutral or first and suggested I take it to a bmw specialist but I'm a single mum and can't afford to do that so need to have an idea of whether this is going to be worth fixing before I spend any more money on it. The car is a 2000 model and has a gas conversion kit on it. It has also developed a leak through all this wet weather and water is pooling in the back passenger side foot well, the mechanic didn't seem to think this was anything to do with the auto problems. Thanks in advance.
What is the mileage. On the vehicle?
Customer: replied 2 years ago.
Thanks for confirming. What exactly was your question? Whether it is worth fixing or not?
Customer: replied 2 years ago.
I was hoping to find out what the fault codes mean and how expensive it is going to be to fix so I can determine if it will be worth my while taking to bmw specialist
Customer: replied 2 years ago.
The mechanics told me the codes relate to pressure actuators and gear box switch but didn't say what this meant in terms of vehicle being fixed. He told me it was ok to drive but I felt dubious about doing that
I will provide an honest answer. I trust this will be appreciated. Please remember that a low rating PUNISHES me for being honest and that I receive nothing for my time until a positive rating is clicked
P0743 - Torque Converter Clutch Circuit Electrical
P0700 - Transmission Control System (MIL Request)
P0078 - invalid
P0748 - Pressure Control Solenoid 'A' Electrical
P0705 - Transmission Range Sensor 'A' Circuit Malfunction (PRNDL input)
these are generic fault codes and can be misleading as they are not bmw specific and sub optimal for transmission diagnostics
it would appear that you have a problem with the position switch and also possibly multiple solenoid issues or bad valve body and possibly a bad torque converter.
I would say the minimum repair cost will be £800 and could run up to £2500 for a complete rebuild or transmission replacement with a used unit
Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.
Customer: replied 2 years ago.
Thanks for your response.In your opinion is the car unsafe to drive?
Please do not forget to click on a positive rating
The car is not unsafe, but you are not doing it any favours driving it in this condition
Please do not forget to click on a positive rating
If there are no additional questions please kindly click on a positive rating
If there are no additional questions, as the question has been answered, please kindly click on a positive rating to ensure I receive proper credit for my time and answer out of the deposit you have already paid
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