PCM Minimum Voltage

[91LS1S10]

Got a question on the minimum voltage that is needed for the PCM. Lately had intermittant stalls. Replaced battery and seems to fix it. Then yesterday it stalled and never could get it to run. Checked voltage was at 12.1 volts. My battery terminal was loose for some reason. Charged up battery and engine fired up. Would appreciate any input.

Rey

[Blacky]

Not sure which PCM you are refering to , but I've run an LS1 PCM successfully on the bench at 9V. However, that was not driving any spark or injectors. It may need more juice than 9V to run the spark/injector hardware.

Regards
Paul

[91LS1S10]

I'm using the 12200411 PCM. It happened again tonight. No DTC set. Will check the crank sensor and wiring tomorrow.

Rey

[joecar]

Should still be able to run at 9V... thats what happens when you first crank... altho it may run from the "edges" of some tables...

Check your power/ground connections for voltage drop.

How old is your alternator (is it worn out)...?

[91LS1S10]

I checked the grounds and measured voltages at the PCM fuses. Looks ok. Alternator is going 2 years now. Voltage is 14.2 when running. Tried starting truck tonight after 2 hours sitting and it starts with no problems. No matter what I did earlier it did not start.