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System Check

Electrical functions of entire system may be checked at multi-pin connector of ECU. Turn ignition off. Unplug multi-pin connector from ECU. Using either ohmmeter or voltmeter, check system between terminals as noted in VANAGON AFC DIGIFANT SYSTEM VOLTAGE and RESISTANCE CHECKS charts. Turn ignition on when testing system.

CAUTION: Connect ohmmeter leads ONLY to terminals as specified in charts to prevent electrical damage to ohmmeter when testing system.
Fig 1: ECU Connector Pin Location
G62165Courtesy of VOLKSWAGEN UNITED STATES, INC.
VANAGON AFC DIGIFANT SYSTEM RESISTANCE CHECKS (1)

Ohmmeter Between Terminals Specification
No. 12 & No. 14
Components Checked Injectors
Specifications Connect only one injector at a time. 15-20 ohms.
No. 6 (2) & No. 11
Components Checked Throttle Valve Switch
Specifications Continuity when closed or fully open.
No. 6 (2) & No. 17
Components Checked Intake Air Sensor
Specifications 500-1000 ohms.
No. 17 & No. 21
Components Checked Intake Air Sensor
Specifications Resistance changes when moving air sensor plate.
No. 6 (2) & No. 8/No. 6 (2) & No. 18
Components Checked Hall Sender Wiring
Specifications Continuity should exist with Hall sender removed and all 3 connectors jumped together.
No. 2 & No. 13
Components Checked Oxygen Sensor Wiring
Specifications Continuity should exist with connector removed from oxygen sensor and Green wire grounded. No continuity with connector installed.
(1) All system checks performed with ignition OFF and ambient temperature of 32-104°F (0-40°C).
(2) NEVER connect test light to this terminal if multi-pin plug is connected to ECU.
VANAGON AFC DIGIFANT SYSTEM VOLTAGE CHECKS (1)

Voltmeter Between Terminals Specification
No. 13 & No. 14/No. 14 & No. 19
Components Checked Control Unit Voltage Supply
Specifications Approximate battery voltage.
No. 13 & No. 25
Components Checked Voltage To Ignition Coil Terminal No. 1
Specifications Approximate battery voltage.
No. 1 & No. 13
Components Checked Voltage To Idle Stabilizer
Specifications Unplug all 4 injectors. Voltage at starter terminal No. 50 when cranking should be minimum 8 volts.
No. 3 & No. 13
Components Checked Voltage To Fuel Pump Relay
Specifications Connect jumper wire between terminals. Fuel pump should operate.
(1) All system checks performed with ignition on and ambient temperature of 32-104°F (0-40°C).
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