Speed-Pro ecm pin -out

[XXQUICK6XX]

If anybody knows this I need to find wire for Battery volts reading low on laptop

Thanks Steve

 

[GCBJCHS]

ecm pinout

Steve,
I had some problems installing a FAST system in my Dad's car. It was a used system with no directions and it had some harness problems. I was lost. I used a GM service manual to get the pin diagram for the factory harness then I used the ol ohmeter to proof through the interface harness to the FAST ecm plug. This enabled me to check inputs from the factory harness. Hope this helps

 

[Glen]

I don't know EXACTLY what you mean by low volts,BUT, the system does not accurately show charging system performance. If you were to do a search, you would find this in other threads. Seems on a fully functioning charging system the FAST shows about 13.8v. What you want to look at is the correction factor for volts, keep it to a minimum. As for charging, use the biggest cable possible. I use a 06 cable from alternator to common post, where I take off for other electrical needs, then the same from common post to battery and picked up .3 volts over a 10 gauge wire.

Anyway, a wiring pinout can be gotten from the FAST website under the install manual.

M1 Batt + Red
H2 9V - No color
H3 9V + No color
L3 12V Ign On Pink

 

[XXQUICK6XX]

Harness

Mine has a custom engine harness and Speed pro is showing about 1 volt lower than the fuse box tapped autometer voltmeter.

Steve

 

[Glen]

It's normal for the FAST to show 13.8 Battery volts even though your meter showed 14.7. Check the Batt Cor %

 

[XXQUICK6XX]

Thanks Glen

Will try this week if it don't snow

Steve

 

[Glen]

If everybody is happy and connected properly you should show 0 correction. If not, look for voltage drop from your source and repair or move to a better source. This is a correction factor used by the ECM, as voltage drops so does injector response, fuel pump operation etc.


I'm not expecting any snow this weekend or next As a matter of fact..... it's a nice cool 79* outside with humidity @ 68%. We are expecting this cool front to pass and be back up into the 80's by turkey day, racing almost year-round

 

[Craig Smith]

Originally posted by Glen
It's normal for the FAST to show 13.8 Battery volts even though your meter showed 14.7. Check the Batt Cor %

This is DEFINITELY not normal. The voltage shown should be exactly what's measured on pin L3.

 

[Glen]

Pin L3 wired to an ignition source, as listed in the install manual, can show 13.8 volts and be normal, dependent on demands put on rest of that circuit. Perhaps it should be wired to the same source that his volt meter uses that is seeing the 14.7 charge. At 13.8v my BattCorr % is 0. Many GM cars run at this voltage, 13.8-14v, as observed using some pretty expensive equipment. I think the important part is the battery correction %.