01What it usually turns out to be
Some module prevents the vehicle from going into rest mode.
02How I actually find it
Current-draw test and ISTA — if codes do not point anywhere, down the matrix to find the leak and which module stays awake.
03Why reading the code alone will not show it
The search direction can be visible; when it is not, the battery-draw test finds it anyway.
04What to do before bringing it in
Make an appointment and have the VIN ready.
Confirmed on cars in this shop.
This is usually diagnostics & electrical troubleshooting
Not sure yet? Send the symptom anyway — I will tell you what it involves for your car.
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