Valves For Camshaft Adjustment, Checking

Required special tools and test equipment
- VAG 1551 Scan Tool (ST) with VAG 1551/3 adapter cable
- Multimeter US 1119 (Fluke 83 or equivalent)
- VW 1594 connector test kit

Function
The camshaft adjustment is dependent on engine speed and load. The electrical solenoid valves for camshaft adjustment (-N205- and -N208-) are switched to apply oil pressure to the mechanical camshaft adjusters, which adjusts the camshaft timing.

Checking
- Connect VAG 1551/1552 Scan Tool (ST) and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with engine running at idle) Refer To On-Board Diagnostics II. Testing and Inspection

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -3- to select "Output Diagnostic Test Mode" function 03.

Indicated on display

Rapid data transfer Q
03 - Output Diagnostic Test Mode

- Press -Q- button to confirm input.

Indicated on display

Output Diagnostic Test Mode ->
Camshaft adjustment 1

- Check using output DTM and activate camshaft adjustment.
Valves 1 and 2 for camshaft adjustment, -N205- and -N208-, must click audibly.

If the valves do not click:
- Check as described in test procedures that follow.

Checking solenoid valves for camshaft adjustment electrically
- Disconnect harness connector from valve.





- Using multimeter with auxiliary wires from VAG 1594, measure resistance across terminals on valve.
Specified value: 10 - 18 ohms

If resistance is not as specified:
- Replace solenoid valve.

Checking voltage supply of valves for camshaft adjustment
- Disconnect harness connector from valve.





- Connect LED tester VAG 1527 between engine ground and terminal 1 of connector (B+).
- Crank starter for several seconds (engine can start).
LED in voltage tester must light up.

If LED does not light up, conduct the following tests:
- Check fuse for valves for camshaft adjustment.
- Check wiring from terminal 1 on 2-pin connector to fuse for continuity per wiring diagram.
- Check fuel pump relay and signal to relay.

Checking signal to valves for camshaft adjustment
- Disconnect harness connector from valve.

- Connect LED tester VAG 1527 between connector terminals 1 and 2.
- Check using output DTM and activate camshaft adjustment
LED must flash.

If LED does not flash or stays on continuously:
- Connect VAG 1598/22 test box to Motronic ECM harness connector and proceed as follows:

If LED does not flash:
- Check wiring from terminal 2 of connector for valve to terminal 55 of ECM/test box for continuity and short circuit to B+.

If LED stays lit constantly:





- Check wiring between valve connector terminal 2 and ECM/test box terminal 55 for short circuit to Ground.
Specified value: max. 1 Ohms.

If the wiring is OK:
- Replace Motronic ECM -J220-.
- Carry out adaptation of throttle valve control module to ECM See page.
- Check readiness code. If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code.

If no malfunction has been found in any of the previous tests:
- Replace respective mechanical camshaft adjuster.