Checking injection timing regulation range: VW 1.9 SDI (AGP, AGR, ALH, AQM, …)

AGR ALH AQM ASV AYQ
The function of the injection timing regulation range is checked in function 04 (Basic settings). In this procedure, the injection commencement valve is pulsed so that the extreme values for advanced (early) and retarded (late) positions for the timing control can be read in measured value block 4, display zone 3.

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
Fault reader V.A.G 1551 (or vehicle system tester V.A.G 1552) with cable V.A.G 1551/3
Adapter set V.A.G 1594
Test box V.A.G 1598/22
Current flow diagram

Test sequence

Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed.
(Connecting fault reader and selecting engine electronics control unit => Page
01-4
.)

Rapid data transfer
HELP
Select function XX
Indicated on display:

Press keys 0 and 4 for the function "Introduction of basic setting" and confirm entry with Q key.

Basic setting
Input display group number XXX
Indicated on display:

Press keys 0, 0 and 4 for "Display group number 4" and confirm entry with Q key.

System in basic setting
4
⇒
880 rpm
advanced
7.9 5 BTDC
66 %
Indicated on display:

Specification in display zone 3 and 4:
advanced 7.0...9.0° BTDC

After approx. 10 seconds the timing device is moved to the retarded position.

System in basic setting
4
⇒
880 rpm
retarded
3.9 5 BTDC
74 %
Indicated on display:

Specification in display zones 3 and 4:
retarded 3.0...5.0° BTDC

Press the ⇒key.
Press keys 0 and 6 for the "End output" function and confirm input with the Q key.
Switch off ignition.

If the specifications are not obtained:

Check commencement of injection valve as follows:

Disconnect 10-pin connector for commencement of injection valve (connection to injection pump metering control).

Measure resistance between connector contacts 9+10.
Specification: 12.0 ... 20.0 ω

If the specification is not obtained:

Replace commencement of injection valve (N108)
=>Page
23-21
, item
19
.
Interrogate fault memory, if necessary, repair any faults and then erase fault memory => Page
01-12
, interrogating and erasing fault memory.

If the specification is obtained:

Connect test box V.A.G 1598/22 to control unit wiring harness.

Check wiring between test box and 10-pin connector for open circuit using current flow diagram.
Contact 9 + socket 79
Contact 10 + socket 2
Contact 10 + socket 28
Wire resistance: max. 1.5 ω
Additionally check wires for short to one another, to vehicle earth and to battery positive.
Specification: ∞ω

If no fault is detected in the wiring:

Replace engine control unit
=> Page
23-134
.