Valve For Camshaft Adjustment, Checking

Valve for camshaft adjustment, checking





Special tools, testers and auxiliary items required
^ Multimeter V.A.G 1526 B or V.A.G 1526 A
^ Voltage tester V.A.G 1527 B
^ Connector test kit V.A.G 1594 C or V.A.G 1594 A
^ Test box 1598/31
^ Vehicle Diagnostic, Testing and Information System VAS 5051 A with diagnostic cable VAS 5051/1





Preparation
Cylinder bank 1 (right)
- Disconnect electrical harness connector - 3 - to Valve 1 for camshaft adjustment -N205-.





Cylinder bank 2 (left)
- Remove bolt from coolant reservoir - arrow -.
- Disconnect electrical wiring from Engine Coolant Level (ECL) Warning Switch -F66- and set aside coolant reservoir with coolant hoses - 1 - and - 2 - connected.





- Disconnect electrical harness connector - 2 - to Valve 2 for camshaft adjustment -N208-.





Checking internal resistance
- Connect multimeter to valve for resistance measurement.
^ Specified value: 8 to 13.

If specified value is not obtained:
- Replace valve.

If specified value is obtained:
- Check voltage supply.

Checking voltage supply
^ Fuse for valve for camshaft adjustment is OK Electrical Wiring Diagrams, Troubleshooting Component Locations.
^ Motronic Engine Control Module (ECM) Power Supply Relay -J271- OK.

Note: Voltage for camshaft adjustment valves is supplied via Motronic Engine Control Module (ECM) Power Supply Relay - J271-.





- Connect voltage tester V.A.G 1527 B as follows:





- Operate starter briefly. *LED must light up

If LED does not light up:
- Check wiring connection from terminal 1 of electrical harness connector via fuse to Motronic Engine Control Module (ECM) Power Supply Relay -J271- for open circuit according to wiring diagram.
- Repair wiring connection if necessary.

If LED lights up:
- Check activation





Checking activation
- Connect voltage tester V.A.G 1527 B to terminals - 1 - (B+) and - 2 - of electrical harness connector.
- Connect Vehicle Diagnostic, Testing and Information System VAS 5051 A and select vehicle system "01 - engine electronics". Ignition must be switched on Guided Fault Finding in VAS 5051 A.





Display on VAS 5051 A:
- In selection - 1 -, click on function "03 - output Diagnostic Test Mode (DTM)".
- Press button repeatedly until Camshaft Adjustment Valve 1 -N205- is actuated.
^ LED must blink
- Press button repeatedly until Camshaft Adjustment Valve 2 -N208-- is actuated.
^ LED must blink
- End function "03 - output Diagnostic Test Mode (DTM)" by pressing button.
- Select "06 - End Output".
- Switch ignition off.
If LED does not blink or if it remains constantly lit:





- Connect test box V.A.G 1598/31 to wiring harness connectors. Engine Control Module (ECM) is not connected. Connect Ground (GND) clip at test box (not visible in illustration) to Ground (GND).

CAUTION: To avoid damaging electronic components, set measuring range before connecting test leads and observe all test requirements.





- Check following wiring connections for open circuit and short circuit to Ground (GND) and B+:
^ Valve 1 for camshaft adjustment -N205-





^ Valve 2 for camshaft adjustment -N208-





- Repair wiring connection if necessary. If wiring connection is OK:
- Replace Engine Control Module (ECM).

If no malfunctions are detected:
- Replace mechanical camshaft adjuster