dgdsm
10+ Year Contributor
- 173
- 4
- Aug 24, 2008
-
Tarzana,
California
So it looks like I have some variation on the infamous Brake + Battery Light problem. I think I may have had it for a while, but only noticing it now, as it goes away on normal driving. A few details:
It usually happens on cold start, occasionally on warm start. If I rev the engine to 1500+ for 1-2 secs after cold start, it goes away. If I go into first gear and drive it these lights go off. Not if I go into reverse though. When these lights are on at idle, the battery is at about 12.3V: definitely not charging. After revving the engine for just a sec or two, it’s usually at 13.5V+ . The P/O told me he had installed a new alternator . It seems like it shouldn’t be going bad in under 2K miles, unless there was something else. It also might be related to idle. Some days, my idle is as low as 650 which is when I tend to see this. On other days, it’s at about 900 and I don’t see these lights on start as much or at all.
Time to shop for a new alternator? There are some threads about the cause being elsewhere. It could be the first signs of a voltage regulator on the blink, as I have seen erratic voltages at the battery in the past. The belts are a bit loose. The P/O had an elaborate sound system which he took out, leaving a lot of loose wires here and there, esp behind the radio. Wires could be moving around and creating intermittent drains or shorts. I know of a used dsm alternator not too far from my area for not a lot of $, but I don’t want to be going through alternators if the problem is actually somewhere else.
It usually happens on cold start, occasionally on warm start. If I rev the engine to 1500+ for 1-2 secs after cold start, it goes away. If I go into first gear and drive it these lights go off. Not if I go into reverse though. When these lights are on at idle, the battery is at about 12.3V: definitely not charging. After revving the engine for just a sec or two, it’s usually at 13.5V+ . The P/O told me he had installed a new alternator . It seems like it shouldn’t be going bad in under 2K miles, unless there was something else. It also might be related to idle. Some days, my idle is as low as 650 which is when I tend to see this. On other days, it’s at about 900 and I don’t see these lights on start as much or at all.
Time to shop for a new alternator? There are some threads about the cause being elsewhere. It could be the first signs of a voltage regulator on the blink, as I have seen erratic voltages at the battery in the past. The belts are a bit loose. The P/O had an elaborate sound system which he took out, leaving a lot of loose wires here and there, esp behind the radio. Wires could be moving around and creating intermittent drains or shorts. I know of a used dsm alternator not too far from my area for not a lot of $, but I don’t want to be going through alternators if the problem is actually somewhere else.