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Deceleration Fuel Shutoff

  1. Ensure engine is at normal operating temperature and no fault codes are stored in ECU memory. Using a digital multimeter and Harness Adapter (VW1315A/1), check voltage at differential pressure regulator.
  2. Connect multimeter to differential pressure regulator. See Figure . Turn ignition on. Control voltage must read positive (+). If voltage reads negative (-), reverse test leads.
  3. Start engine. Raise RPM to 3000 and release throttle. Control voltage must momentarily switch to negative (-). If system fails test, perform electrical tests. See CIS-MOTRONIC VOLTAGE & RESISTANCE TESTS chart. See Figure . If system electrical tests are okay, replace ECU. Clear fault codes.
CIS-MOTRONIC VOLTAGE & RESISTANCE TESTS

Test Procedure Specification
Test Step No. 1
Connection Terminals 14 & 35
Test Conditions (Addition Steps) Ignition "ON"
Test Values About Battery Voltage
Test Step No. 2
Connection Terminals 17 & 35
Test Conditions (Addition Steps) Ignition "ON"
Test Values About Battery Voltage
Test Step No. 3
Connection Terminals 32 & 35
Test Conditions (Addition Steps) Ignition & A/C "ON"
Test Values About Battery Voltage
Test Step No. 4
Connection Terminals 33 & 35
Test Conditions (Addition Steps) Ignition & A/C "ON"
Test Values About One Volt Below Battery Voltage
Test Step No. 5
Connection Terminals 19 & 35
Test Conditions (Addition Steps) Ignition "ON"
Test Values About Battery Voltage
Test Step No. 6 (1)
Connection Terminals 13 & 35
Test Conditions (Addition Steps) Insert Fuel Relay Fuse
Test Values FIL Must Light
Test Conditions (Addition Steps) Ignition "ON"
Test Values FIL Must Light
Test Step No. 7
Connection Terminals 4 & 5
Test Conditions (Addition Steps) Ignition "OFF"
Test Values 15-25 Ohms
Test Step No. 8
Connection Terminals 3 & 35
Test Conditions (Addition Steps) Ignition "OFF"
Test Values 2500 Ohms @ 68°F (20°C)
Test Values 200 Ohms @ 212°F (100°C)
Test Step No. 9
Connection Terminals 31 & 35
Test Conditions (Addition Steps) Throttle Closed
Test Values Open (No Continuity)
Test Conditions (Addition Steps) Throttle Wide Open
Test Values Continuity
Test Step No. 10
Connection Terminals 28 & 35
Test Conditions (Addition Steps) Throttle Closed & Open
Test Values Continuity
Test Step No. 11 (2)
Connection Terminals 18 & 35
Test Conditions (Addition Steps) N/A
Test Values Continuity
Test Step No. 12
Connection Terminals 13 & 35
Test Conditions (Addition Steps) Insert Fuel Relay Fuse
Test Values Continuity
Connection Terminals 13 & 35
Test Conditions (Addition Steps) Ground Test Connector
Test Values Continuity
Test Step No. 13
Connection Terminals 14 & 16
Test Conditions (Addition Steps) N/A
Test Values About 10 Ohms
Test Step No. 14
Connection Terminals 14 & 15
Test Conditions (Addition Steps) N/A
Test Values 30-60 Ohms
Test Step No. 15
Connection Terminals N/A
Test Conditions (AS) Unplug Hall Effect Sensor Connector
Test Values N/A
Connection Terminals 30 & 35
Test Conditions (AS) Terminals 1 & 2 To Hall Effect Sensor
Test Values Continuity
Connection Terminals 30 & 21
Test Conditions (AS) Terminals 2 & 3 To Hall Effect Sensor
Test Values Continuity
Test Step No. 16
Connection Terminals 11 & 35
Test Conditions (AS) Remove Terminal From Power Output
" Stage Of Coil. Ground Center Contact
Test Values Continuity
Test Step No. 17
Connection Terminals N/A
Test Conditions (AS) Disconnect KS Harness Connector
Test Values Open (No Continuity)
Connection Terminals 6 & 8
Test Conditions (AS) Connect Terminals 1 & 2
Test Values Continuity
Test Conditions (AS) Connect Terminals 1 & 3
Test Values Continuity
Test Step No. 18
Connection Terminals 7 & 35
Test Conditions (AS) Disconnect O2 Connector & Ground
Test Values Continuity
Test Step No. 19
Connection Terminals 23 & 26
Test Conditions (AS) Sensor Plate In Rest Position
Test Values About 5000 ohms
Test Step No. 20
Connection Terminals 26 & 35
Test Conditions (AS) Sensor Plate In Rest Position
Test Values About 4000 ohms
Test Step No. 21
Connection Terminals 34 & 35
Test Conditions (AS) Standard Transmission
Test Values Continuity
Test Conditions (AS) Automatic Transmission In "P" Or "N"
Test Values Open (No Continuity)
Test Step No. 22
Connection Terminals 12 & 35
Test Conditions (AS) Remove Fuel Pump Relay And Ground
" Terminal No. 47 Of Fuse Panel Relay
Test Values Continuity
(1) California only.
(2) Non-California only.
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