I have a 2007 Land Rover LR2/ Freelander 2 i6. The car is stalling and has no power, mechanic seems to think I need to buy a new fuel pump. Before buying one, I thought it would be a good idea to do some testing to eliminate wiring and electrics. So here's where I'm stuck now: - On the Fuel pump control module itself, I get 12+ volts on the pwr input from the relay, I have a good ground against batt -ve coming into the unit, I have a good steady 12+ volts output to the fuel pump, then I have a 'dynamic -ve outputting to the fuel pump. The fifth terminal is dancing around 5V coming from the ECM. -I call the -ve dynamic because it is dancing, at around the same voltage as the ECM signal measured against Ground, +ve feed to pump, -ve batt terminal as well as +ve batt terminal. -Is this the normal operation of the module? -Are these the proper ranges of voltages for these units?
ALL THIS IS CART BEFORE HORSE STUFF.!
1- fuses are first blown
2: scan the PCm is next ,after all if PCM detects spark dead it cuts fuel dead in blink if an eye,(as in no crash and burn as seen on TV)
3: if above is not helping (no DTCS) the we,,
we check fuel pressure on the rail, cranking or at idle.
if out of spec we check FPR and the PUMP voltage.
if pump is dead, 0 PSI (bar) we check voltage to the pump actual
12vdc good or 0v bad, below 11volts bad or battery is weak.!
that is how all EFI is tested,not guessing, not discovering pins the PCM that
floats (ever hear of tri-state logic)
the output of a pcm or computer or any logic module can be
1; 0V GROUND DRIVEN STATE
2: 12v or 5vdc drivenstate
3: or floating, as in not used now and floats to save energy.
best is work from a service manual and no guess and the real schematic.
what matters is,
1: NO DTCs for spark dead, (p0300 is weak spark not dead)
2: pump pressure at spec, cranking and at idle of can be sustained.
3: if pressure fails cranked (a 2 man test) and 12vdc is on the 2 pins of pump cranked then the pump /FPR is bad.
if voltage is wrong at the pump we work backwards to the point of failure on those 2 wires, pump feed.
that how this is done, and not taking a bath in fuel tank dropped on a whim.
SOURCE: Fuel pump relay will not
if you ground the tan/light green wire at the relay or at the EEC IV self test conector will the pump run then? and if the pump runs will the engine start?
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