Hi,

I have a problem with my Discovery 2 TD5. The air mass sensor is not giving any values. After evaluating the problem I noticed that there are no values in the MAF. The pin 1 and 2 o 3 (12v) have no connection problem, the cabling is good. I made the following test to evaluate the cabling. I measured the continuity of the two pins to ECU pin 11 and 20. The continuity is assured, validated if the other wiring pins have continuity to see the signal pass to them and have a cable problem, and all seems okay.

Then I evaluated the behavior of MAF. What I found was, when I have only the ignition on the 12v are correct and the others 2 pins have the right residual values, I assessed the continuity of MAF pin 1 to the mass and was guaranteed. After putting the car to work, pins 1 and 2 go to ZERO and the continuity to the mass in pin 1 ceases to be verified. The mass is made by the centralina, it seems to me that it is the ECU that is cutting the mass for some reason. I suspect a mass passage somewhere but I have not been able to identify the problem yet. I have tested with several ECU and the behavior is always the same.

Thank you.

Hi,

Have you plugged it into a diagnostic unit and seen the live values as you are driving?

Cheers

neilly said:

Hi,

Have you plugged it into a diagnostic unit and seen the live values as you are driving?

Cheers

Click to expand...

It gives no values.

Then , I would suggest swapping for a known good one if you can and seeing what you get.

Cheers

neilly said:

Then , I would suggest swapping for a known good one if you can and seeing what you get.

Cheers

Click to expand...

I´ve done that already. It gives no values. Could it be a earth problem?

might be chaffed wiring between the MAF and fusebox or bad contact in the fuse cavity(F2) which goes to open under load .