With Manufacturer's Scan Tool

Mass Air Flow (MAF) sensor, checking

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551/1552 Scan Tool using VAG 1551/3 Adaptor cable
- VAG 1598/22 Test Box
- Fluke 83 multimeter
- VW 1594 Adaptor kit
- Wiring diagram

Requirements







- Fuse 43 must be OK.
- ALL electrical consumers switched OFF
- A/C switched OFF, if installed.
- Automatic Transmission Range selector lever in "P" or "N"
- Engine Coolant Temperature 85 °C minimum See Display group 04, Display field 3

Test sequence
- Connect VAG 1551/1552 Scan Tool. [1][2][3][4]Reading and Clearing Diagnostic Trouble Codes
- Start engine and let idle.
- Press 0 and 1 buttons to select "Engine Electronics" address word 01.

Indicated on display (example only)


06A906018AB Motronic M5.9.2 HS V06 ->
Coding 00000 WSC 00000

- Press -> button.

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons 0 and 8 to select "Read Measuring Value Block" function 08.
- Press Q button to enter input.


Indicated on display


Read measuring value block
Input Display group number XXX


- Press buttons 0, 0 and 2 for "Display group 2."
- Press Q button to enter input.


Indicated on display (1 to 4 = Display fields).


Read measuring value block 41 ->
1 2 3 4


- Check load specifications, Display fields 2 and 3.







If specification obtained
- Press -> button.

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons 0 and 6 to select "End output" function 06.
- Press Q button to enter input.
- Switch OFF ignition.

Display group 2, evaluating







Mass Air Flow sensor power supply, checking







- Disconnect 5-pin harness connector -1- from Mass Air Flow sensor -2-.
- Connect multimeter using aux. cables from VW 1594 to measure voltage at terminal 2 (connector to ECM).
- Start engine and run at idle.
- Measure voltage between terminal 2 and body ground.
- Specification: 11.5 Volts minimum
- Switch OFF ignition.

If specification not obtained:
- Check wiring connections from terminal 2 to fuse relay panel using Wiring diagram

Mass Air Flow sensor signal wire, checking







- Connect VAG 1598/22 Test Box to Control Module wiring harness.







- Check wiring for open circuit between Test Box and 3 pin harness connector using Wiring diagram.
Terminal 4 + socket 11
Terminal 5 + socket 13
Terminal 3 + socket 12
Wire resistance: 1.5 Ohms maximum


- Also check wires for shorting to one another.
- Specification: Infinity Ohms

If the Voltage supply and wirings are OK:
- Replace Mass Air Flow sensor G70.
- Display the Readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
- If DTC memory was erased or if the ECM was disconnected from Battery + , set the Readiness code. Monitors, Trips, Drive Cycles and Readiness Codes