With Generic Scan Tool

Valves For Camshaft Adjustment (Vehicles With Engine Code BDF), Checking

Function
The camshaft adjustment is load-and RPM dependent. The electrical valves for camshaft adjustment switch oil pressure onto camshaft adjusters (mechanical adjustment mechanisms), which then adjust the camshafts.

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirements







- The respective fuses of the Valve -1- for camshaft adjustment -N205-and Camshaft Adjustment Valve 1 (exhaust) -N318- must be OK.
- Fuel Pump (FP) Relay -J17- must be OK, check.
- Battery voltage must be at least 11.5 volts.
- All electrical consumers like, for example, lights and rear window heating must be switched off.
- Parking brake must be engaged or else daylight driving lights will be switched on.
- For vehicles with automatic transmission, selector lever must be in position -P-or -N-.
- If vehicle is equipped with an A/C system, it must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Ignition switched off.

Test sequence







- Disconnect 2-pin harness connector to the respective valve for camshaft adjustment:
1 - Valve -1- for camshaft adjustment -N205-
2 - Camshaft Adjustment Valve 1 (exhaust) -N318-

NOTE: Before disconnecting harness connectors, mark allocation to component.







- Measure resistance between terminals of the respective valve for camshaft adjustment.
Specified value: 10...18 Ohms

If specified value is not obtained:
- Replace control housing for camshaft adjustment, item3.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.
Diagnostic Mode 4: Reset/Erase Diagnostic Data

- Generate readiness code.
Monitors, Trips, Drive Cycles and Readiness Codes

If specified value is obtained:
- Connect test box to control module wiring harness, connect test box for wiring test.
Test Box, Connecting For Wiring Test







- Check wires between test box and 2-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Wire resistance: max: 1.5 Ohms







- Also check wires for short circuit to B+ and Ground (GND).
Specified value: Infinity Ohms
- Check wire between 2-pin connector terminal 1 and Motronic Engine Control Module (ECM) Power Supply Relay -J271- for open circuit according to wiring diagram
Wire resistance: max: 1.5 Ohms

If resistances and wires are OK:
- Replace Motronic Engine Control Module (ECM) -J220-.