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System Check

Electrical system functions may be checked at multi-pin connector of ECU. Turn ignition off. Disconnect connector from ECU. Using either ohmmeter or voltmeter, check system between terminals as noted. See Fig 1 . See VANAGON AFC DIGIFANT SYSTEM VOLTAGE CHECKS  table and VANAGON AFC DIGIFANT SYSTEM RESISTANCE CHECKS  table.

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 VOLTAGE CHECKS (1)

Between Terminal Nos. Components Checked Specifications
13 & 14 Control unit voltage supply Approximate battery voltage
14 & 19 Control unit voltage supply Approximate battery voltage
13 & 25 Voltage to ignition coil terminal 1 Approximate battery voltage
1 & 13 Voltage to idle stabilizer, unplug all 4 injectors Voltage at starter terminal 50 when cranking should be minimum 8 volts.
3 & 13 Voltage to fuel pump relay. Connect jumper wire between terminals Fuel pump should operate.
(1) All system checks performed with ignition off and ambient temperature of 32-104° F (0-40°C).
VANAGON AFC DIGIFANT SYSTEM RESISTANCE CHECKS (1)

Between Terminal Nos. Components Checked Specifications
12 & 14 Injectors. Connect only one injector at a time 15-20 ohms.
6 & 11 Throttle Valve Switch Continuity when closed or fully open.
6 & 17 Intake Air Sensor 500 - 1000 ohms
17 & 21 Intake Air Sensor Resistance changes when moving air sensor plate
6 & 8 Hall Sender Wiring Continuity should exist with Hall sender removed and all 3 connectors jumped together
6 & 18 Hall Sender Wiring Continuity should exist with Hall sender removed and all 3 connectors jumped together
2 & 13 Oxygen Sensor Wiring 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 on and ambient temperature of 32-104° F ( 0-40° C).