ashtray

iTrader: (12)

Any ideas where my 1992 sc400 might have a short? The car is tip top but she keeps draining batteries even with a new alternator. We've gone through several batteries and my mechanic could use our help. Any thoughts are appreciated. Could it be the fuel pump ecu?

SC400slide

iTrader: (11)

How fast is the battery draining? 2 weeks without any use is the usual for SC's batteries to drain, with an alarm system.

ashtray

iTrader: (12)

About 2-3 days. It gets driven daily. Completely stock no alarm.

SC400slide

iTrader: (11)

Could be a number of things then. From ECU to Starter magnetic switch.
First I'd check would be engine grounds. Look for any corrosion on the terminals. Test the battery with an ohmmeter for grins to make sure it isn't an output issue. Don't know how short term it can cause as quickly, but if your PS fluid leaks abundantly that could be ruining your Alternator. Fat chance tho.
Here is a helpful thread. More of a long-term drainage though.
https://www.clublexus.com/forums/per...g-battery.html
GL.

bigwhite

This is the closet thread to post the fact that yes my tip-top SC400 will drain a battery in 2-4 weeks in the winter.