Alfa Romeo Forums banner

"GENERAT" Lights Up When FSC Activated

850 Views 2 Replies 2 Participants Last post by  ianmac
I just spent a while this weekend adjusting my cam timing, then the timing then the SPICA. After shortening the gap a fair amount and getting everything running quite nicely (my intake cam was out by about 5 vernier holes, screwing everything up) I have noticed a rather strange syndrome. Whenever I take my foot off the gas, the "GENERAT" light comes on, then goes out when the RPM drops to about 1200. This seems to correspond to when the FCS solenoid would be activated. I checked the voltage between the wire at the FCS and the FCS itself, and it reads about 4v when the solenoid should be activated (though maybe it isn't coming up to 12 volts since it takes a while for the reading to stabilize and the RPM drops pretty fast with no load on the engine and me hanging over the engine compartment).

The light comes on even if I am going at 4000 rpm down the highway and just take my foot off the gas for a second. Goes off right away if I step on the gas. The light still comes on if I disconnect the FCS at the FCS wire.

What does this suggest? The car has a new battery and alternator. This syndrome is new.

Do I have a short in my microswitch leaking to ground?
1 - 3 of 3 Posts
I think you have a short or something in the microswitch. Although, I would think that the fuse would blow. Try disconnecting the microswitch wire at the connector on the right side of the engine compartment and check the light again.

If it's indeed a bad microswitch, just leave it disconnected until the next time you have the injecition pump off the engine. If it's properly tuned, you don't need the FCS circuit. Mines been inop for a couple years now.
Something fishy....

Roadtrip, I measured the voltage going _to_ the microswitch, and it is ~4volts. Very strange. The FCS works fine, energizes when jumpered to the battery and cuts the engine when idling. I pulled the fuse from fuse number 6, which goes to the FCS, but this fuse also powers the generator light, so this wasn't very helpful as a diagnostic!! I'm thinking either that I have a bizarre short to ground, a poor contact in the wire going to the FCS, or that my newly rebuilt (off Ebay) alternator has blown a diode. I'll check the DC and AC voltage off the alternator tomorrow night, that should tell me if my alternator is OK.
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.