PSM and ABS errors can be set when the battery is changed. The loss of power...

The warning lights "psm off" and "abs" recently turned on in my 2003 base boxster. I first noticed it after having to drive in reverse for about 200 feet on a gravel road on a fairly cold night (maybe 15F outside). I don't know if that could be related, but thought I'd throw it out there since coldness seemed to play a role in this for a few others when I googled it. Other people seemed to think that a new battery fixed their problem (not so in my case - mine was getting old so I replaced it with no change) or that some sensor should be replaced. I'm sort of at a loss for how to diagnose/repair the problem. I plugged in a code reader while the warning lights were on and found no codes. The two lights pop on after a few blocks every time I drive the car now. Anyone have any ideas?

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Steve (Iowa)
The warning lights "psm off" and "abs" recently turned on in my 2003 base boxster. I first noticed it after having to drive in reverse for about 200 feet on a gravel road on a fairly cold night (maybe 15F outside). I don't know if that could be related, but thought I'd throw it out there since coldness seemed to play a role in this for a few others when I googled it. Other people seemed to think that a new battery fixed their problem (not so in my case - mine was getting old so I replaced it with no change) or that some sensor should be replaced. I'm sort of at a loss for how to diagnose/repair the problem. I plugged in a code reader while the warning lights were on and found no codes. The two lights pop on after a few blocks every time I drive the car now. Anyone have any ideas?

plays a role. When I changed the battery in my 03 996 apparently I did it quick enough no errors were set but I was told at the dealer when I went there to return the old battery for credit and have my "handiwork" inspected by a tech that often times errors appear after a battery R&R. (At the dealer auxiliary power is used to prevent this.)

The errors can be cleared by a diagnostics computer or just driving the car will clear them.

In your case though the warning lights come on when you drive the car. This suggests then there's something else going on that is not related to the interruption of battery power.

If it has been snowy/icy where you are and you've been driving the car in it the ice/slush that accumulates in the wheel wells can melt from the heat of the car when parked up in a garage and this melt water runs down and freezes on various hardware. When you move the car this breaking up of this can damage wiring. Or a connector has just developed a marginal connection.

Not sure what you can do other than inspect the wheels/hardware. Trouble is you do not know from which corner the error comes from. Thus it would probably be to your benefit to have the error codes read. An OBD2 code reader/data viewer is as you have found out is not going to read these codes. The controllers that have these errors are behind a gateway or perhaps on a different bus. The Porsche diagnostics computer can get to these of course, and I believe Durametric can too.

Knowing the error codes and from where they are coming from would be a big help in your attempt to resolve this on your own.

I had the ABS light coming on intermittently in my 2003 S. It was a wheel sensor not correctly seated.

After noticing that the brake lights didn't seem to respond to the pedal, I went into the upsidedown ninja position and fiddled with the brake pedal switch. One of the cheaper solutions was to sort of jiggle it as it can get stuck. That seems to have done the trick. Oh and Marc, the problem started up before the battery replacement, but thanks for that tip. Shame that my cheapo OBD2 code reader can't read the code that goes with this.

should just replace it. My 02 Boxster's brake light switch wore out. The initial symptom was the brake lights would come on when the brakes were applied then switch off. Then the brake lights just never came on.

However, I never had any warning lights appear.

While you are in the upside down ninja position changing the brake light switch have a clutch interlock switch handy too and replace it.

My Boxster's clutch interlock switch started acting up and the engine would not crank without some wild stomping on the clutch pedal.

I whole heartedly agree -- those switches are cheap enough that if it's acting unusual, replacement is in order. Soon, it shall be done.