Hot film air mass sensor - check electrics - ME-SFI fuel injection system

AD07.61-P-6000-04C

Hot film air mass sensor - check electrics - ME-SFI fuel injection system





Scope of test

Tester/test connection

Operation/

Prerequisite:

Specified value

 Possible cause/

Remedy

1.0



Hot film mass air flow sensor (B2/5)

Hot film signal

104 

(48E)

N3/10





 103

(47E)

Ignition: ON:

Engine: At idle speed:

Coolant temperature

> 70 °C

0.9 - 1.1 V

1.3 - 1.7 V

(increasing rpm, increasing voltage)

 1.1

 1.2

 1.3

 Line

 Unmetered air

 B2/5

1.1

Voltage supply
5 V

N3/10



104 

(48E)



B2/5

 4

Unplug coupling on hot film air mass sensor (B2/5) and check directly at socket 4 brown/yellow (br/ge)

Ignition: ON

4.7 - 5.2 V

 Line

 N3/10

1.2

Ground lead for hot film air mass sensor (B2/5)

B2/5

3 



N3/10



 102

(46E)

Unplug coupling on hot film air mass sensor (B2/5) and check directly at socket 3 brown (br)

Ignition: ON

4.7 - 5.2 V

 Line

1.3

Voltage supply
12 V

N3/10



104 

(48E)



B2/5

 2

(2)

Unplug coupling at hot film air mass sensor (B2/5) and connect positive end of voltmeter to socket 2 red/blue (rt/bl)

Ignition: ON

11 - 14 V

 Line

 Models 129 and 140

Base module (N16/1) or fuse in base module

 Model 202

Fuse and relay module (K40/4)

 Model 210

Relay module (K40)