With Generic Scan Tool

EGR Vacuum Regulator Solenoid Valve, Checking

Recommended special tools and equipment
- VAG1390 hand vacuum pump

Test sequence
- Remove engine cover.
- Unclamp connecting pipe between charge air cooler and exhaust pipe at exhaust pipe.
- Disconnect vacuum hose at EGR vacuum regulator solenoid valve.
- Connect V.A.G 1390 hand vacuum pump to valve.







- Operate hand vacuum pump and observe diaphragm rod.
Diaphragm rod must move in direction of arrow.
- Disconnect hose of hand vacuum pump from EGR valve.
Diaphragm rod must move back in opposite direction of arrow into the original rest position.

Checking EGR Vacuum Regulator Solenoid Valve

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

Test requirements







- The respective fuses of Diesel-Direct fuel injection system must be OK.
- Battery voltage must be at least 11.5 Volts.
- No leaks on intake or exhaust side.
- Vacuum hoses must be properly sealed.







- Disconnect connector at solenoid valve for Exhaust Gas Recirculation (EGR).







- Measure resistance between terminals of valve.
- Measure resistance at valve.
Specified value: 14...20 ohms


NOTE: Resistance at room temperature is in lower specified range, resistance at operating temperature is in upper specified range.


If specified value is not obtained:
- Replace EGR Vacuum Regulator Solenoid Valve -N18-.
- Erase DTC memory of control module for Diesel-Direct fuel injection system, Diagnostic mode 4: Reset/erase diagnostic data.
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If specified value is obtained:
- Switch ignition on.







- Measure voltage supply of valve at connector terminal 1 and at engine Ground (GND).
Specified value: approx. battery voltage
- Switch ignition off.

If specified value is not obtained:
- Connect test box to control module wiring harness, connect test box for wiring test.


Vehicles with 80-pin control module







- Check for open circuits in wires between test box and harness connector according to wiring diagram.
Terminal 1 + socket 2+28
Terminal 2 + socket 29
Wire resistance: max. 1.5 ohms

Vehicles with 121-pin control module







- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 1 + socket 1 and 2
Terminal 2 + socket 61
Wire resistance: max. 1.5 ohms

Continuation for all vehicles
- Also check wires for short circuit to each other, to vehicle Ground (GND) and to B+.
Specified value: Infinity Ohm

If no malfunctions are found in wires:
- Replace Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248-
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes