Fuel Pump Relay Control Circuit....
#1
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Fuel Pump Relay Control Circuit....
Guys
I'm fighting an issue with a swap I'm currently working on. Using a 411 PCM and a 5.3 block/heads with LS1 accessories.
I'm using a techrods 99-02 LS1 standalone harness, so there was very minimal wiring that needed to be done. I do not have anything wired to the transmission yet.
I have powered up the ECM via the cars ignition, connected with HPT and licensed the PCM, disabled VATS and EGR. I have not touched anything else with the tune. I made sure to perform a VATS write as well.
I cannot get the fuel pump to prime or run.
The odd thing here is that I can use the VCM scanner to enable the pump and it runs just fine. Also when the VCM suite connects to the ECM it cycles the pump just like it should on prime.
Am I missing something within the PCM configuration? Or am I missing an input the PCM needs to see in order send out voltage to activate the fuel pump relay?
Thanks
I'm fighting an issue with a swap I'm currently working on. Using a 411 PCM and a 5.3 block/heads with LS1 accessories.
I'm using a techrods 99-02 LS1 standalone harness, so there was very minimal wiring that needed to be done. I do not have anything wired to the transmission yet.
I have powered up the ECM via the cars ignition, connected with HPT and licensed the PCM, disabled VATS and EGR. I have not touched anything else with the tune. I made sure to perform a VATS write as well.
I cannot get the fuel pump to prime or run.
The odd thing here is that I can use the VCM scanner to enable the pump and it runs just fine. Also when the VCM suite connects to the ECM it cycles the pump just like it should on prime.
Am I missing something within the PCM configuration? Or am I missing an input the PCM needs to see in order send out voltage to activate the fuel pump relay?
Thanks
#2
mmm.. sounds like you missed something. If I remember correctly the ecu needs a signalled pulse from the regulator in order to determine whether a 3 second prime signal needs to be sent to the fuel pump. If the ecu doesn't receive the pulse it determines whether it receives a Vcc signal in the run position of the key switch. Thats what i'd be checking for first.