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System Testing

Following VOLTAGE CHECKS and RESISTANCE CHECKS charts show procedure for checking CIS-E system components from ECU connector. ECU connector terminal numbers are called out in testing procedures. Ignition MUST be off whenever ECU connector is disconnected or reconnected. Use care to avoid any terminal damage when testing, removing or attaching connectors.

Always check all connections used in test procedure. If readings are incorrect, disconnect terminals and determine if wiring or components are at fault. High tension lead should be disconnected at ignition distributor end and connected to ground. Use Digital Multimeter (US 1119 ).

THERMO-TIME SWITCH - OPERATIONAL TIME

Temperature Seconds
-4°F (-20°C) 5-11
14°F (-10°C) 4-9
32°F (0°C) 3-7.5
50°F (10°C) 2-6.5
68°F (20°C) 1-4
86°F (30°C) 0-2
104°F (40°C) 0
FOX CIS-E INJECTION - RESISTANCE CHECKS (1)

Terminal Nos. Components Checked Specifications
2 & 15 Ground Connection Reading of zero ohms
9 & 15 Ground Connection Reading of zero ohms
7 & 8 O2 Sensor Shield Reading of zero ohms
2 & 8 O2 Sensor & Wiring Reading of zero ohms with Green O2 lead disconnected and grounded. If not, Green wire has open.
2 & 8 O2 Sensor & Wiring Reading of infinity ohms with Green O2 lead connected to harness. If not, O2 is defective and should be replaced.
10 & 12 Differential Pressure Reg. & Wiring Reading of 17.5-21.5 ohms. If not, check wire 10 or 12 for open. If wires are good, differential pressure regulator is defective and should be replaced.
14 & 17 Potentiometer & Wiring Reading of less than 1000 ohms with airflow sensor plate in rest position. If not, check wires 14, 17, and 18 for open. If wires are good, adjust or replace potentiometer.
17 & 18 Potentiometer & Wiring Reading of more than 4000 ohms. If not, check wires 14, 17, and 18 for open. If wires are good, adjust or replace potentiometer.
2 & 21 Temperature Sensor & Wiring Reading of 2.5k ohms at 68°F (20°C). Lower ohm reading below 68°F or higher above 68°F. If readings are incorrect, check ground line (wire 21) between intake manifold and ECU. If wiring is good, temperature sensor is defective and should be replaced.
(1) TESTING CONDITIONS: Always disconnect ECU with ignition off. Disconnect main ECU connector behind glove box. Wiring connectors on temperature sensor, potentiometer, and differential pressure regulator must be connected. Set multimeter to 20k ohm scale. Prevent ohmmeter damage by checking ONLY terminals listed.
Fig 1: Fox - ECU Connector
G61261
VOLKSWAGEN - (16 VALVE) INJECTION VOLTAGE CHECKS (1)

Terminal Nos. Condition/Procedure Specifications
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 to full on position Battery voltage
2 & 13 Ignition on. Throttle at idle position, ensure idle switch is on Battery Voltage
2 & 24 Operate Starter Minimum 8 Volts
2 & 25 Use LED Tester (US 1115), operate starter LED must flicker. Test Hall signal from ignition control unit.
2 & 6 (2) With ignition on, switch on A/C Battery voltage
2 & 16 (2) With ignition on, switch on A/C Battery voltage
2 & 19 (2) With ignition on, switch on A/C Battery voltage
(1) TESTING CONDITIONS: Disconnect CIS-E ECU connector with ignition off. Remove high tension lead from ignition distributor coil and connect to ground. Set multimeter to 20-volt DC scale.
(2) Vehicles With A/C.
Fig 2: ECU Connector - Terminal PIN Numbering
G61262
VOLKSWAGEN - (16 VALVE), INJECTION RESISTANCE CHECKS (1)

Terminal Nos. Components Checked Specifications
2 & 7 N/A Continuity
2 & 9 (2) N/A Continuity
2 & 15 N/A Continuity
2 & 20 N/A Continuity
2 & 8 Disconnect O2 sensor, ground Green wire Continuity
2 & 8 Reconnect O2 sensor Infinity ohms
10 & 12 N/A 17.5-21.5 ohms
14 & 17 N/A Less than 1K ohms
17 & 18 N/A Greater than 4K ohms
2 & 21 (Temperature Sensor) See Temp. Sensor Testing
(1) TESTING CONDITIONS: Disconnect CIS-E ECU connector with ignition off. Set multimeter ohm scale.
(2) Connect to terminal No. 22 on Jetta GLI (16 Valve).
GOLF GTI & JETTA GLI - INJECTION SYSTEM VOLTAGE CHECKS (1)

Terminal Nos. Components Checked Specifications
1 & 2 Voltage Supply To ECU Battery voltage with ignition on. If not, check fuse 18. If fuse good, check open ground circuit between intake manifold and ECU.
1 & 2 Voltage Supply From Starter Minimum of 8 volts with starter cranking. If not, check wiring to 15 and "X" terminals reversed on relay board. See wiring diagram.
2 & 3/No.2 & 4 Idle Stabilizer Control Valve & Wiring Battery voltage with ignition on. If not, check middle (voltage supply) wire of connector for control valve. If center wire good, wire 3 or 4 to control valve is open. If wiring is good, control valve is defective and should be replaced.
2 & 5 Full Throttle Switch & Wiring Battery voltage with ignition on and full throttle switch actuated. If not, check middle (voltage supply) wire of connector for throttle switch. If center wire good, wire 5 to full throttle switch is open. If wiring is good, full throttle switch is defective (due to no continuity) and should be replace.
2 & 13 Idle Switch & Wire 13 Battery voltage with ignition on and idle switch activated by throttle lever. If not, wire 13 to idle switch is open. If wire good, idle switch is incorrectly adjusted or bad.
2 & 6 A/C Voltage Signal Battery voltage with ignition and A/C on. If not, check A/C fuse. If good, check wiring bridge between wires 6 and 16. Check wires 16 and 19 to A/C.
2 & 16 A/C Voltage Signal Battery voltage with ignition and A/C on. If not, check A/C fuse. If good, check wiring bridge between wires 6 and 16. Check wires 16 and 19 to A/C.
2 & 19 A/C Voltage Signal Battery voltage with ignition and A/C on. If not, check A/C fuse. If good, check wiring bridge between wires 6 and 16. Check wires 16 and 19 to A/C.
2 & 24 Wiring Between Starter & ECU Minimum 8 volts with starter cranking. If not, check wire 24 for open. If wire is good, starter solenoid switch is defective and should be replaced.
2 & 25 Hall RPM Signal & Ignition ECU Voltage display must fluctuate with starter cranking. If not, check wire 25 to ignition ECU for open. If wire 25 good, check wiring between ignition distributor and ignition ECU. If wiring is good, Hall sensor is defective and should be replaced. If wiring and Hall sensor are good, ignition ECU is defective and should be replaced.
(1) TESTING CONDITIONS: Disconnect and ground high tension lead at ignition distributor end. Unplug ECU connector with ignition off. Set multimeter to 20-volt DC scale.
GOLF GTI & JETTA GLI - INJECTION SYSTEM RESISTANCE CHECKS (1)

Terminal Nos. Components Checked Specifications
2 & 15 Ground Cable Bridge Reading of zero ohms
2 & 9 M/T Models Only Reading of zero ohms
2 & 22 A/T Models Only Reading of zero ohms
7 & 2 O2 Sensor Wire Shield Reading of infinity ohms
2 & 8 O2 Sensor & Wiring Reading of zero ohms with Green 02 lead disconnected and grounded. If not, Green wire has open.
2 & 8 O2 Sensor & Wiring Reading of infinity ohms with Green O2 lead connected to harness. If not, O2 is defective and should be replaced.
10 & 12 Differential Pressure Reg. & Wiring Reading of 17-22 ohms. If not, check wire 10 or 12 for open. If wires are good, differential pressure regulator is defective and should be replaced.
14 & 17 Potentiometer & Wiring (2) Reading of less than 1000 ohms with airflow sensor plate in rest position. If not, check wires 14, 17 and 18 for open. If wires are good, adjust or replace potentiometer.
17 & 18 Potentiometer & Wiring (2) Reading of more than 4000 ohms with airflow sensor plate lifted away from rest position. If not, check wires 14, 17, and 18 for open. If wires are good, adjust or replace potentiometer.
2 & 21 Temperature Sensor & Wiring Reading of 6k ohms at 32°F (0°C). Reading of 2.5K ohms at 68°F (20°C). Reading of 300 ohms at 176°F (80°C). If readings are incorrect, check ground line (wire 21) between intake manifold and ECU. If wiring is good, temperature sensor is defective and should be replaced.
(1) TESTING CONDITIONS: Disconnect and ground high tension lead at ignition distributor end. Unplug ECU connector with ignition off. Set multimeter to 20k ohm scale. Prevent ohmmeter damage by checking ONLY terminals listed.
(2) Potentiometer terminals No. 1, 2 and 3 are connected respectively to terminals No. 18, 17 and 14 on ECU connector.
QUANTUM 5-CYLINDER RESISTANCE CHECKS (1)

Terminal Nos. Components Checked Specifications
2 & 22 Ground Bridge Reading of zero ohms. If not, check for open in bridge across terminals.
2 & 15 Ground Bridge Reading of zero ohms. If not, check for open in bridge across terminals.
7 & 8 O2 Sensor Wire Reading of infinity ohms. If not, check for open circuit in O2 sensor lead.
2 & 8 O2 Sensor Wiring Reading of zero ohms with Green O2 sensor lead unplugged and grounded. If not, check for open in circuit in Green O2 sensor lead.
10 & 12 Differential Pressure Reg. & Wiring Reading of 17.5-21.5 ohms. If not, check for open in circuit between regulator and ECU. If wiring is good, replace differential pressure regulator.
14 & 17 Potentiometer & Wiring Reading below 12 k/ohms with airflow sensor plate in rest position and altitude sensor unplugged. If not, check wiring to terminals 14 and 17 for opens. If wiring is good, adjust or replace airflow sensor plate potentiometer.
17 & 18 Potentiometer & Wiring Reading above 35 k/0hms with airflow sensor plate in rest position and altitude sensor unplugged. If not, check wiring to terminals 14 and 17 for opens. If wiring is good, adjust or replace airflow sensor plate potentiometer.
18 & 14 Altitude Sensor Reading of 21-26 k/ohms with potentiometer unplugged. If not, check for open circuit in wiring. If wiring is good, replace altitude sensor.
11 & 14 Altitude Sensor Reading of 200-38,000 ohms with potentiometer unplugged. If not, check for open circuit in wiring. If wiring is good, replace altitude sensor.
21 & 2 Temperature Sensor Reading of 2.5 k/ohms at 68°F (20°C). Resistance reading should be higher at lower temperatures and lower at higher temperatures. If not, check for open circuit in wiring. If wiring is good, replace temperature sensor.
1 & 5 Full Throttle Switch Reading of zero ohms with switch in full throttle position. Reading of infinity with full throttle switch in closed position. If not, check wiring for open circuit. If wiring is good, adjust or replace full throttle switch.
1 & 13 Idle Switch Reading of zero ohms with switch in idle position. Reading of infinity with switch in any open throttle position. If not, check wiring for open circuit. If wiring is good, adjust or replace idle switch.
(1) TESTING CONDITIONS: Disconnect and ground high tension lead at ignition distributor end. Unplug ECU connector with ignition off. Set multimeter to 20-k/ohm scale. Prevent ohmmeter damage by checking ONLY terminals listed.
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