A8L V8-4.2L (BFM) (2004)
Fuel Pump Relay: Testing and Inspection
Fuel Pump (FP) 2 Relay -J49-, Checking
Fuel Pump (FP) 2 Relay -J49-, Checking
NOTE: Fuel pump (FP) Relay 2 is located in relay- and fuse holder in luggage compartment, right side, relay position 3.
Check voltage supply of Fuel Pump (FP) Relay 2
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Remove Fuel Pump (FP) 2 Relay -J49- from relay position 3.
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Switch ignition on.
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Connect V.A.G 1526 portable multimeter in sequence between terminals 3 (B+, terminal 15) and 2 (Ground -GND-) as well as 1 (B+, terminal 30)
and 2 (Ground -GND-) of relay socket.
Specified value: approx. battery voltage respectively.
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If no battery voltage is displayed, measure plus terminals to vehicle Ground (GND) as a test.
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If there is still no battery voltage, check plus wires (terminal 15/terminal 30) for open circuit.
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If battery voltage is displayed when measuring to vehicle GND and not at terminal 2, check wire connection from terminal 2 via fuse (in relay- and
fuse holder in luggage compartment, right side) to Fuel Pump (FP) -G6-.
Checking activation of Fuel Pump (FP) relay
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Connect V.A.G 1527 voltage test lamp between terminal 3 (B+, terminal 15) and 4 (Ground (GND)-activation of Engine Control Module (ECM)).
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When switching on ignition, voltage test lamp must light up for approx.1 second and then go out. When operating starter, voltage test lamp must
light up constantly.
NOTE: Voltage test lamps with low current draw do not go out completely after 1 second, but rather light up weakly until starter is operated.
If voltage test lamp now lights up, replace Fuel Pump (FP) 2 Relay -J49-.
If voltage test lamp does not light up, check wire as follows:
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Connect V.A.G 1598/31 test box to wiring harness of Engine Control Module (ECM) See: Computers and Control Systems/Testing and
Inspection/Reading and Clearing Diagnostic Trouble Codes/Scan Tool Connecting
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Connect portable multimeter between terminal 5 of relay socket and socket 45 of test box and check wire connection for continuity.
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If specified value is not obtained, check wire connection for open circuit or short circuit.
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If there is no open circuit and voltage test lamp does not light up, replace Engine Control Module (ECM) and generate readiness code again.
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Read readiness code If DTC memory was erased, readiness code must be generated again.