0411PCM 5v input 12v output at certain range
Posted: Wed Jun 15, 2022 7:16 am
Hi All,
My LS1 build is running short of vacuum for the brakes and I've purchased a VF UP28 electric vacuum pump and also got a hold of the Bosch 20876799 vacuum switch to turn the pump on and off.
Unfortunately it seems instead of this running a 12v out line to trigger the pump, it looks to use the PCM to control when the pump turns on.
Seems like a stupid idea to me, but anyway, it uses a 5v in, ground reference and an output wire back the PCM.
My guess is on the E39a PCMs and similar ones the OS has a table of sorts that basically says when the voltage reaches x then send 12v (or ground) to a relay, when the voltages goes back to y, shut it off.
Is there a table in the 0411 PCMS (currently using HPT RTT 1 Bar SD OS) that could be utilised to monitor the voltage (Vacuum at the sensor) and send a signal to engage the pump via relay?
If there's a solution to this other than fork out $150 for a CVR or Aeroflow branded pressure switch it would be preferable.
My LS1 build is running short of vacuum for the brakes and I've purchased a VF UP28 electric vacuum pump and also got a hold of the Bosch 20876799 vacuum switch to turn the pump on and off.
Unfortunately it seems instead of this running a 12v out line to trigger the pump, it looks to use the PCM to control when the pump turns on.
Seems like a stupid idea to me, but anyway, it uses a 5v in, ground reference and an output wire back the PCM.
My guess is on the E39a PCMs and similar ones the OS has a table of sorts that basically says when the voltage reaches x then send 12v (or ground) to a relay, when the voltages goes back to y, shut it off.
Is there a table in the 0411 PCMS (currently using HPT RTT 1 Bar SD OS) that could be utilised to monitor the voltage (Vacuum at the sensor) and send a signal to engage the pump via relay?
If there's a solution to this other than fork out $150 for a CVR or Aeroflow branded pressure switch it would be preferable.