autobahn_clem

Hello all,
I just installed an LT1 out of a '95 Roadmaster into my '84 GMC, it went rather well, no real big mods to manage; however my problem is the alternator has quit charging, i just installed a new alternator and still nothing. I replaced it for two reasons, first no charge, second bearings were driving me crazy. Anyway, red wire from battery to the rear of the alternator, and two brown wires from the plug, they appear to go toward the ECU, but i assume one goes to the ECU and the other to the instrument panel lamp (dummy light). What must i do to make this function?
Also, what can i do to pull the codes from this OBD1 ECU?
Thanks in advance!!

97LT1

iTrader: (3)

So you have no voltage output from the alt? Try a different one.

autobahn_clem

This is the second one; today i was helped by a person well knowledged, he showed me what i have suspected; the brown wires need some sort of connection. One wire must have some sort of dummy light to display, i.e. exciter or activator of the regulator. I know this because he connected a test light, clip end to the positive side of the battery, and then probed the wires. One wire "excited" the alternator, the other maybe backfed to the radiator fans (of which i have been having issues with).
So i figure i am going to trace the wire (brown) inside the cab where the instrument panel connector is, and connect a bulb to it, of course I will connect it on the switched side, otherwise it will not shut off when the engine is off.
As for the fans, well not sure yet.... does anyone know if these are controlled by the ECU??? will it have a negative effect if i bypass the ECU and regulate the temp myself???
Any good advise will be GREATLY appreciated.

Thanx