System Check
CAUTION:
To prevent electrical damage to ohmmeter when testing system, connect ohmmeter leads ONLY to terminals as specified in charts.
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 AFC DIGIFANT SYSTEM VOLTAGE and RESISTANCE CHECKS charts.
On California models equipped with Digifant II system, an "On-Board Diagnostic System" is used. Trouble codes/fault memory can be read through the "Check" indicator switch which illuminates when a fault is detected and stored in memory or by activating fault memory. To activate fault memory/code(s), turn ignition switch to "ON" position, engine off. Depress "Check" indicator switch for at least 4 seconds. Indicator light on switch will start flashing codes. A flash code consists of 4 flash impulse groups, with a maximum of 4 flash impulse per group. Between each impulse group there is a 2.5 second pause between codes.
To erase fault codes from memory, turn ignition switch to "OFF" position, press and hold down indicator switch and turn ignition switch to "ON" position. Continue depressing switch for about 5 seconds and turn ignition switch off. Test drive vehicle for a minimum of 10 minutes. Recheck codes and correct if necessary. Repeat fault erasing procedure until memory is cleared.
FAULT/TROUBLE CODES - DIGIFANT II
| Flash Code |
Circuit Affected |
| 2312 |
Coolant Temperature Sensor |
| 2322 |
Intake Air Temperature Sensor |
| 2232 |
Airflow Sensor Potentiometer |
| 2142 |
Knock Sensor |
| 2342 |
Oxygen Sensor |
| 4444 |
No Fault(s) in Memory |
| 0000 |
End of Test Sequence |
Courtesy of VOLKSWAGEN UNITED STATES, INC. VANAGON AFC DIGIFANT SYSTEM RESISTANCE CHECKS
| Ohmmeter Between Terminals |
Specification |
| No. 12 & No. 14 |
| Components Checked |
Injectors |
| Specifications |
Connect only one injector at a time. 15-20 ohms. |
| No. 6
& No. 11 |
| Components Checked |
Throttle Valve Switch |
| Specifications |
Continuity when closed or fully open. |
| No. 6
& 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
& No. 8/No. 6
& 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. |
VANAGON AFC DIGIFANT SYSTEM VOLTAGE CHECKS
| 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. |