MAF P0102 fault

[juskavas]

Hi,I have a problem with my Seat Leon 2006 1.9 TDI (BXE).

Fault code:
P0102 – MAF signal too low.
Fault appears only when engine is running (comes back right after clearing).
MAF value is stuck at ~550 mg/str (doesn’t change with RPM).

What I’ve done:
Replaced MAF with new Bosch no change.
Checked wiring from MAF to ECU continuity OK.
5V reference present.
12V supply sometimes missing/intermittent.
Tried giving direct +12V and ground from battery still same problem.
EGR/DPF deleted long ago, no issues before.

What else could cause this? Wiring under load? Bad ground? Or ECU issue?
Thanks

 

[mty12345]

Could be a pin fitment issue. Maybe the connector terminals have been spread apart and arent contacting the MAF pins properly

 

[juskavas]

Could be a pin fitment issue. Maybe the connector terminals have been spread apart and arent contacting the MAF pins properly

Well, I changed the connector and checked the voltage again. It turned out there was no 12V (blown fuse). I replaced it — now everything is good. But pin 5, I guess, is the signal. When I test it with a multimeter (pin 5 to battery -), it shows 0.6–0.9 mV on the DC 200 mV setting, so basically nothing. I guess the signal wire is broken most likely. I will try to connect it directly from the ECU to the MAF.