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Pin Voltage Charts

VAG 1598 TEST CONNECTOR PIN VOLTAGE CHECK

Terminals Component To Be Tested & Condition Value or Result
13 & 14 Voltage Supply (Control Unit), Ign. ON Battery Voltage
14 & 19 Voltage Supply (Control Unit), Ign. ON Battery Voltage
3 & 13 (Jumper) Wires To Fuel Pump Relay, Ignition ON Pumps Must Run Audibly
1 & 25 (M/T) Wires From Starter Terminal 50 Ign. OFF, Operate Starter 8 Volts Minimum
19 & 25 (A/T) Wiring To Starter Lockout Relay Ignition ON, Select "P" Then "N" Battery Voltage
" " Wiring To Starter Lockout Relay, Ign. ON Select "1", "2", "3", "D" & "R" No Voltage
1 & 19 Voltage To Control Unit, Ignition On Battery Voltage
19 & 35 Voltage To Control Unit, Ignition On Battery Voltage
1 & 6 Wires To Coil, Ignition On Battery Voltage
1 & 4 Fault Indicator Light, Ignition On Battery Voltage
1 & 23 Idle Stabilizer Valve, Ignition On Battery Voltage
1 & 24 (Jumper) Wires To Fuel Pump Relay, Ignition On Pumps Must Run Audibly
1 & 20 Wiring To Injector - Cyl. No. 1 (1) Battery Voltage
1 & 21 Wiring To Injector - Cyl. No. 2 (1) Battery Voltage
1 & 3 Wiring To Injector - Cyl. No. 3 (1) Battery Voltage
1 & 2 Wiring To Injector - Cyl. No. 4 (1) Battery Voltage
28 & 34 Throttle Potentiometer (Power), Ign. ON 4.5-5.0 Volts
33 & 28 Throttle Potentiometer Connected, Ignition On, Throttle Setting: Idle 0.3-1.7 Volts
33 & 28 Throttle Potentiometer Connected, Ignition On, Throttle Setting: WOT 3-5 Volts
28 & 38 Hall Sender (Power), Ignition ON 10 Volts Min.
37 & 38 Hall Sender (Signal), (2) Ignition OFF Operate Starter LED Must Flicker
1 & 6 Ignition Signal Function, (2) Ignition Off Operate Starter LED Must Flicker
(1) With Ignition ON and fuse No. 18 removed, jump terminals No.1 and 24 together.
(2) With ignition off, use LED Tester (US 1115) with Adapters (VW 1594) instead of multimeter. Disconnect harness from fuel rail (main injector connector). Perform test only if engine will not start.
ECU CONNECTOR PIN VOLTAGE CHECK

Terminals Component To Be Tested & Condition Value or Result
1 & 2 Ignition ON Battery Voltage
2 & 3 Ignition ON Battery Voltage
2 & 4 Ignition ON Battery Voltage
2 & 5 Ignition ON, Operate Full Throttle Switch Battery Voltage
2 & 13 Ignition ON, Operate Throttle Idle Switch Battery Voltage
2 & 6 Ignition & A/C On Battery Voltage
2 & 16 Ignition & A/C On Battery Voltage
2 & 19 Ignition & A/C On Battery Voltage
2 & 24 With A/C Ignition Off, Operate Starter 8 Volts Minimum
2 & 25 With A/C Hall Sender (Signal), (1) Ignition Off, Operate Starter LED Must Flicker
(1) Connect LED Tester (US 1115) instead of DVOM (US 1119).
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