Lots of people damage pcm transistors by connecting wrongly to ECU.
Here’s an example of reading a BMW Bosch engine ECU EDC17C06 with PCM. Failed to read on bench, with 14V power supply.
Using this pinout
If you use OBD for power supply, please do not plug in a separate 12V, otherwise, it will cause the device transistor or step-down chip to burn.
If you use your own lab power and voltage regulator. You don’t know how device power works. Just adjust the voltage to 13.5 or whatever you think will cause the whole triode to burn out.
Tips before changing resistor:
If you get problem on identify and reading, just remove power supply of pcm tuner box.
And make another source of power and ground, and it works perfectly. No need to change resister.
Solution:
Replace PCM transistors. PCM package comes with spare transistors used for GPT circuits.
Make sure the device and ecu connection via bench cable is proper before changing.
Select the correct protocol (ECU model) in pcmflash software when reading or writing ECU.
Customer Solution:
Resoldered two transistors K1P, and work bench mode. One soldered K1P other analog p1P, I had only one K1P
replace first this transistor, K1P, analog 1P,p1P
k1p mmbt2222a – 0.6A 40/75V and p1p pmbt2222a – 0.8A 40/75V
Read on bench module 71 successfully.
All work, edc17cp45, edc17c06 tested bench mode module 71
If not working after replacing these transistors, check other transistor positions below:
- N1 transistor: with MMUN2113LT1G
- N2, N3 transistor: with MMUN2211LT1G
- Q3 Q9 Q10 Q11: MMBT222A-7-F
The corresponding positions are marked below:
- Q3, Q9, Q10, Q11 transistor: with MMBT2222A-7-F
The corresponding positions are marked below:
UPDATED:
Some people have some problems with pcm module 71 even after changing the transistors, they still don’t read module 71. In the PCM Flash App, in the settings, the option “Use other GPT outputs pins with PCM hardware” was enabled, and it must be disabled, confirm yours.
It should work after changing the transistors and deactivating this option.
