how do you check for a bad fuel controller

[kbflip02]

anyone....i have intermittent problems with the pump going in and out and ive already replaced the pump 3 times....as of right now the fuel pump controller is completely bypassed and the pump is constantly running as long as the car is but im wondering how to trouble shoot my controller because im thinking that might be whats causing the problem...oh well any info would be appreciated...on a side note happy fathers day to all you dads

-k

[Q45tech]

Similar to one on Q45. The usual failure modes are crystalized solder connections, burmed discolored connectors, or actually exploded internal components.

Every electric motor slows down with age as the commutators oxidize and corrode. As these motors slow down the current increases which overheats the circuitry.

All starts from waiting too late to replace the fuel pump, stressing FPCU until one of 3 speed ranges fail. Replacing pump without replacing FPCU!

Dealers have learned the hard way from bad come backs that both units should be replaced in tandem.

Having replaced 2 fuel pumps on mine and hundreds of others we always recommend changing both units.

I always carry a spare FPCU as one of my dozens of road trip spares.