90CS Quattro V6-2.8L (AFC) (1995)
Fuel Injector: Testing and Inspection
Electrical Checks
CHECKING ELECTRICAL RESISTANCE
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Disconnect harness connector from fuel injector to be tested.
Fuel Injector Testing
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Measure resistance of fuel injector.
Specification:
Bosch 15.0-17.0 ohms
Siemens 13.5-14.5 ohms
If the specified value is not obtained:
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Replace fuel injector.
CHECKING BATTERY POSITIVE VOLTAGE FOR FUEL INJECTORS
REQUIREMENTS
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Fuel pump relay OK
^
Activation of fuel pump relay OK
^
Injector valve circuit breaker -S72- OK (red holder in electronics box in passenger side footwell)
PROCEDURE
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Disconnect harness connector from fuel injector to be tested.
2-Pin Connector
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Connect US 1115 LED tester or equivalent between connector terminal 2 and Ground (GND).
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Use On-Board Diagnostics (OBD) Output Diagnostic Test Mode (DTM) to activate fuel pump relay -J17-.
^
LED must light up
If the LED does not light up:
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Check wiring connection for continuity between connector terminal 2 and circuit breaker -S72- (red holder in electronics box in passenger side
footwell) according to wiring diagram.
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Repair if necessary.
If the LED lights up:
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Check activation of fuel injectors.