Pinout Values and Diagnostic Parameters

DESCRIPTION
The following checks use the VW 1594 Test connector kit, VAG 1527B LED tester or equivalent and a digital volt/ohm meter (DVOM) in conjunction with the VAG 1598 Pin Out Box. Refer to Tools and Equipment for test equipment specifications.

NOTE: There are Pin Out testers that are available from other manufacturers that will work for these tests. The socket numbers on the VAG 1598 correspond directly to the Engine Control Module (ECM) connector pin numbers.

Use the VW 1594 adaptor kit to make connections between the Test Box, LED tester and DVOM.

The values given are valid within an ambient temperature range of 0°C to 40°C (32°F to 104°F).

If measured values differ from the specifications; check the wiring to the component using the wiring diagram before replacing the component, especially for values specified at less than 10 ohms in which case the resistance measurement for the component should be repeated.

If a measured value only deviates slightly from the specified value, clean the tester terminals, connectors and measuring wires and then repeat the test.

CAUTION: Switch multimeter to the appropriate measuring range BEFORE connecting the test leads to avoid damaging sensitive electronic components.

To connect the testers to the Test Box, use jumper cables from the VW 1594 adaptor kit.

In addition to the tests described in the table, check the wiring for short to Ground (GND) or Battery Positive Voltage (B+) as necessary.

REQUIREMENTS
- Battery voltage OK.
- Fuses 18 and 21 OK.
- Ground connections on engine and transmission OK (engine ground connection: on support for upper intake manifold).
- Fuel pump and fuel pump relay OK.

CONNECTION
- Switch ignition OFF.
- Disconnect harness connector from Motronic Engine Control Module.

CAUTION: Ignition must be switched OFF before disconnecting engine control module. After switching OFF ignition, allow 20 seconds for the hot wire in the Mass Air Flow (MAF) sensor to heat up and self clean.

- Connect adaptor cable VAG 1598/18 between the Test Box and engine control module harness connector.
- The ECM is left disconnected.

NOTE:
- On vehicles with automatic transmissions, performing electrical checks will generate and store malfunctions in the Diagnostic Trouble Code (DTC) memory, which must be erased. See DTC Memory.

- Some test steps included in the following charts are for components that are not on all vehicles, i.e. EGR Sensor, Air Pump relay, etc.

- Perform the electrical checks using the VAG 1598 Test charts.