I have an GEN IV E38 ECM running my 408 LS. The wiring harness was made by Speartech. I am using a complete Holley LS Engine Swap Accessory Drive Systems Part #20-138 that includes a 130 amp alternator. The engine is swapped into a 2001 Chevrolet S10. I removed the stock S10 ECM that ran the original V6. The truck died over the weekend. In the scan file (NOT attached because it is huge), I can see the voltage to the ECM drop from 13 something down to about 6 volts. Before it died, the GM 4L85E Supermatic transmission was not shifting correctly , the radio came on and off, and the truck was acting weird.
I had the truck jumped started, but it was clear the battery either 1). wasn't being charged by the alternator, or 2). the battery was totally junk and would not accept a charge, or 3). wiring to/from the battery/alternator was loose etc, or 4). some combination of #1 and #2 and #3.
Wiring at battery, master disconnect switch, starter and alternator etc looks fine. With a new battery installed, I am only getting 11.something volts. After some research, I found that the ECM might control the alternator on this setup. Here are the two settings that I see in HP Tuners:
SYSTEM > GENERAL > ALTERNATOR > VOLTAGE CONTROL
SYSTEM > GENERAL > ALTERNATOR > ECM OVERRIDE
My tune shows "Not Fitted" and "Disabled" for Voltage Control and ECM Override respectively. Tune file and screen shot attached.
Would simply changing the VOLTAGE CONTROL and ECM OVERRIDE to "Fitted" and "Enabled" fix my problem? I am expecting to see 13.6 volts to 14.5 volts during normal operation.
I'm reading up on the subject, but I'm not understanding the whole deal yet. If someone wants to chime in with a educated response, I would appreciate it.