Operation CHARM: Car repair manuals for everyone.
Home >> Audi >> 2004 >> A8L Quattro Sedan (4E8) V8-4.2L (BFM) >> Repair and Diagnosis >> Relays and Modules >> Relays and Modules - Powertrain Management >> Relays and Modules - Fuel Delivery and Air Induction >> Fuel Pump Relay >> Testing and Inspection >> Fuel Pump (FP) Relay -J17-, Checking

Fuel Pump (FP) Relay -J17-, Checking



Fuel Pump (FP) Relay -J17-, Checking







NOTE: Fuel Pump (FP) relay is located in relay- and fuse holder, relay position 4 in front right footwell.

Check voltage supply of Fuel Pump (FP) relay
- Remove Fuel Pump (FP) Relay -J17- from relay position 4.
- Switch ignition on.
- 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.
- If no battery voltage is displayed, measure plus terminals to vehicle Ground (GND) as a test.
- If there is still no battery voltage, check plus wires (terminal 15/terminal 30) for open circuit.
- 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 instrument panel, right side) to Transfer Fuel Pump (FP) -G23-.

Checking activation of Fuel Pump (FP) relay
- Connect V.A.G 1527 voltage test lamp between terminal 3 (B+, terminal 15) and 4 (Ground (GND) activation of Engine Control Module (ECM)).
- 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) Relay -J17-.

If voltage test lamp does not light up, check wire as follows:
- Connect V.A.G 1598/31 test box to wiring harness of Engine Control Module (ECM). Scan Tool Connecting
- Connect portable multimeter between terminal 4 of relay socket and socket 65 of test box and check wire connection for continuity.
- If specified value is not obtained, check wire connection for open circuit or short circuit.
- If there is no open circuit and voltage test lamp does not light up, replace Engine Control Module (ECM) and generate readiness code again
- Read readiness code. If DTC memory was erased, readiness code must be generated again
pro multis · About Operation CHARM