Tricky P0102 error

[Pajo]

Hi Everyone,

I'm hoping somebody might be able to help with what is becoming a difficult to solve P0102 error code. The car is a manual Diesel 2013 SR5 (KUN26R with 1KD-FTV engine) with about 240k on the odometer. I've only had it a few months and recently had it serviced (not by Toyota), it seems to have been pretty well cared for. Last week I went to start it after a few days of non usage and the engine light came on and after driving about 100m i noticed the VSC off light was also flashing. It starts fine but has no power when trying to drive it. I used an OBD2 scanner with the 'car scanner' app which gave me error code P0102 with C1201. My first thought was rodent damage but cannot find any sign of chewed wires.

I cleaned the MAF sensor, checked for blockages to the air filter intake, replaced the air filter, checked voltage at the sensor connector, insulation on all wires to earth as well as between the wires, continuity (buzzed but didn't measure resistance) from ECU to the sensor, replaced the MAF sensor. The replacement sensor is OEM bought from a Toyota dealer. Error codes were cleared after each step but they return immediately. I also tried disconnecting the battery to clear codes but that made no difference. I have inspected the air hose on the engine side of the MAF sensor for leaks but it looks good. It seems to me like the MAF P0102 code is a symptom not cause but don't know to what check next.

I had a mechanic come and take a look and he said he thought it could be an ECU problem because with the engine running, when he disconnected the connector to the MAF, there was no change to the airflow reading (which he said was zero) and he expected that the ECU would set the Airflow to Max. He also said it is an hard error being thrown as it appears as soon as the car is started even after having been cleared. When I use my OCB2 reader to check the sensor value it says 2.6 which never changes, even with the engine off and only the ignition on.

Can anyone confirm what value I should see for the MAF sensor with it disconnected?

Any ideas on what I should be doing next would be much appreciated.

[dave g]

Check the small filter at the throttle body the main filter and make shore the tube that feeds it is not blocked where it is inside the throttle body that is what happened to mine can't remember the code that came up.
I ended up cleaning the hole egr shit of a job.

[Pajo]

Thanks for the reply. I have now found the problem which is slightly embarrassing but I thought I would post in case anyone has a similar issue. The answer was rodent damage. The sensor end of the MAF output wire (where I checked it) had perfect insulation however I made the mistake of checking continuity of that output wire to the ecu by connecting the sensor end of the wire to earth and then checking at the ecu end that the wire had continuity to earth. The problem was that where the rodent chewed through the wire, it left the sensor side open circuit and the ecu side grounded so what looked like continuity to the sensor connector was in reality only continuity to the rodent damage. Ah well, time to take off the intercooler and repair the wire.

Anyone like to advise on whether to solder or crimp the repair? I have a soldering iron but would need to buy a crimper

[dave g]

Definitely solder and shrink rape

[Rob_Wood]

The answer was rodent damage. The sensor ... The problem was that where the rodent chewed through the wire, ... was in reality only continuity to the rodent damage. Ah well, time to take off the intercooler and repair the wire.

Anyone like to advise on whether to solder or crimp the repair? I have a soldering iron but would need to buy a crimper

Hhmmm,
Sensing a theme here. Haven't suffered this myself (YET) but I'm guessing it's only a matter of time, I've noticed others mention rat & mice issues before. I park mine out in the whether and I am just wondering if anyone might have a rock solid way to prevent this particular type of hassle?
Mods, please feel free to post this in a new topic if you think it's worth the effort. I'm just bored and wondering what others might think about this one.