I'm baffled - I have a 2006 WRX STI that has very recently started to do some very weird things.
Here's what happens with the dash lights:
While driving at any speed the emergency brake and ABS lights will flicker on for a split second. They don't stay solid, just blink on then off. Sometimes it's just one blink, sometimes it's a few in a row, but not at any discernible pattern. I'm about 85% sure it happens more when the car hits smallish bumps, but it has also blinked on when I know the road is smooth.
There's another set of lights that I just noticed today too: emergency brake, battery, and rear diff light. Those seem to flicker when the car hits bumps, and doesn't seem to have any other pattern.
The brake/ABS thing seems to happen more often when it's a bit cold.
Perhaps related - when starting the car, it sometimes acts nuts. With the key in the on position (prior to turning over the engine), things will seem normal, then everything can totally die, then be right back to normal again.
Prior to all this happening I replaced the alternator with a refurbished one. I replaced the battery at the same time.
Here's what I've been able to test:
- after sitting for a few days, I've checked battery voltage - 12.7 volts.
- I've checked for parasitic draw using a multimeter in circuit with the car completely off, doors closed (aside from open hood). There was minimal draw. A few milliamps at most.
- I've removed an aftermarket stereo install, suspecting grounding issues
- I've checked ground connections on the engine and at a few places inside
- I've checked fuses - none are blown.
- I've checked voltage while the engine is running. If I recall, it was close to 14 volts. I'm pretty sure I also checked current while idling but can't recall for sure.
What should I do next? I don't mind taking it to a dealer if I need to, but I want to have a good idea of what the problem could be before I go in. If their diagnosis is similar to ideas folks might have here I think I'll trust the dealer more.