"MAF circuit low input": flatline/zero (0. g/s) reading.

[Distendo]

P0102 code (lambda light on)
ODBC 'airflow rate' live readout is flatline zero (0. g/s).

Otherwise engine runs sweet (apart from recent tendency to very occasionally cut out when idling, and very briefly 'hesitate' when under load... I've cleaned the idle air control valve: thread here). The PCV kit is new.

Taking car tomorrow to local indy Volvo mechanics.
Just wondering if there's anything I can check myself.

This completely zero reading suggests to me that either the MAF sensor has failed completely (it was new only 90k miles ago ) or there's a wiring fault (I've cleaned the plug connector and don't fancy trying to find where the wiring goes), but could some issue elsewhere cause this fault code and zero reading?

I gather that MAF codes can be caused by a filthy blocked air filter (I think unlikely in this instance*), a filthy MAF sensor (*ditto), or a leak in some (vacuum) hose somewhere (I spray tested - used WD40 as it was what I had to hand - but no pick-up).

Suggestions welcomed!

[cheshired5]

Check the plug contacts with ignition on.
As well as the battery voltage I have 2 x 5V signal voltages as my MAF includes the intake air temperature sensor so yours may vary.

These are my working MAF wiring figures from a post I made in a D5 thread but the principles are the same.

Originally Posted by cheshired5

These are mine.



Meter Positive on Positive Post No Key
Meter negative probing
1 Battery voltage
2 Battery voltage
3 Battery voltage
4 Battery voltage
5 Battery voltage

Meter Positive on Positive Post Ignition on
Meter negative probing
1 Battery voltage
2 6.8
3 Battery voltage
4 0.005
5 6.8

Meter Negative on ground No Key
Meter Positive probing
1 0v
2 0v
3 0v
4 0v
5 0.010v

Meter Negative on ground Ignition On
Meter Positive probing
1 0.0007
2 4.99
3 0.006
4 Battery voltage
5 4.99