|
|
|
|
|
|
|
|
Test
|
TECH 1
|
Notes
|
Nominal Values
|
Pin
|
Possible
|
|
Step
|
Display
|
|
|
|
Trouble
|
|
No.
|
|
|
|
|
Codes
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
07
|
AIR FLOW SENSOR
|
Engine at idle speed,
|
0.5 to 1.5 V
|
7/26
|
73, 74
|
|
|
|
operating temperature
|
|
|
|
|
|
|
|
|
|
|
Trouble-shooting: Nominal
Value: Cause of Fault:
(If nominal value is not
attained)
A general distinction must be
made here between air flow meters with idle CO pot. (5 plug terminals occupied)
and without idle CO pot. (4 plug terminals occupied). There are therefore also
different terminal assignments, see relevant circuit diagram.
· Ignition ON
· Remove air flow
meter 0.1 to 0.3 V · Short circuit of signal lead Ter. 2
plug (signal
lead) with Ter. 3 (+)
· Control unit
defective
· Bridge Ter. 3 (+)
with Ter. 2 on > 4.2 V · Lead interruption or short circuit
air flow meter plug using adapter to
ground from
cable from KM-609 -
Control unit Ter. 12 (+) to AFM Ter. 3
- Control unit Ter. 7 (signal
lead) to
AFM Ter. 2
·
Control unit defective
· Check voltage
between > 4.9 V · Lead interruption from control unit
Ter. 3 (+) and Ter. 4 (-) on Ter.
26 (-) to AFM Ter. 4
air flow meter plug with multimeter
If nominal values are attained · Air flow meter electrically defective
·
Air valve jams (note stress marks)
·
Carry out noise check
Air flow meter checking values: (see
next page)
Ter. 2 (signal lead)/Ter. 4 (-): 8
to 2500 W
Ter. 3 (+)/Ter. 4 (-): 300
to 550 W
Note: The terminal designations are located
under the rubber grommet of the AFM plug.
AFM Noise Check
Testers: Opel Tester or Multimeter MKM-587-A
Test: Adapt air flow meter terminals 2, 3 and 4 with cables
from KM-609.
Example: Test with Opel Tester
- Red checking cable to AFM Ter.
2 (signal lead)
- Black checking cable to AFM
Ter. 4 (ground)
- Tester adjustment:
"MULTI", "U", "Spez." (special input),
"%", "10V"
- Connect black terminal to
battery negative terminal
- Ignition ON
- Open air valve slowly and
regularly
Nominal Value: 0.17 to 4.9 V and oscilloscope diagram 1
AFM is defective if signal corresponds to oscilloscope
diagram 2
|
|
|
|
Oscilloscope diagram 1
The horizontal line travels
up the screen as the air valve opens and then returns to the start position.
|
Oscilloscope diagram 2
If the horizontal line is
interrupted or irregular, the AFM is defective.
|
