So my car has been plugged in for several weeks now that winter is starting. Today it's pretty nice out and I unplugged from charger to take it out for a spin. Unplugged the charger from the cigarette lighter and notice the charger was blinking. After I unplugged it from the wall (not sure if leaving it would be bad on car) I started it up.

Upon starting I got an error code about past failure and the switches wouldn't work. I restarted to see if it would clear and then a msg about psm failure came on. Tuned the car off and searched this forum to see what happened. I understand after battery is reconnected it can throw off these messages and driving a bit can help. Has anyone had this problem after being plugged in for a time? Anything I should do about charger or is this normal?? I am a bit nervous about driving on regular roads w the driver aids not working. Don't want something to kick in randomly and maybe cause a problem either. But I have never plugged the car in before and not sure if this is normal or not.

 

No issue, drive and it will reset itself.

Peace
Bruce in Philly

 

I do not think you have a real problem but I do have a couple of comments....

1. When unplugging the car from a battery maintainer, instructions are generally to unplug from the wall and then unplug from the cigarette lighter socket.

2. How old is your car battery? When my car battery was approaching its last legs, it would often indicate it was checking the PASM system just after the engine started. It stopped doing that when I put a new car battery in.

 

I have had my PASM light come on after service requiring the battery to be disconnected. I see that you said PSM, but I'm assuming that as Bruce said, it should clear after driving a while.

 

Thank you for heads up on disconnecting from wall first. I missed that part in instructions. Battery is less than 1yr old so didn't think that would be an issue but you never know.

I drove it last night and all messages cleared within a couple of blocks. Thanks for the quick responses. Really had me nervous at first.

 

I had PSM (not PASM) Failure light along with some other warnings when battery was low. Once recharged, it fixed itself.

 

Since you indicate the battery charger was flashing and then you received the PASM failure message, you might actually have a battery problem. Not knowing what type of battery charger you're using, it's hard to know. Neither the OEM charger (made by CTEK) nor the Battery Tender brand flash when fully charged - they have a steady green light. Flashing lights often indicate a battery issue, like it won't charge or polarity is reversed. If it's not a sealed type (Optima) are the cells properly filled with fluid? If not, top up with distilled water.

 

Uh oh, just took my steering wheel off (disconnected battery first) then put the loaner core back on and go PSM and PASM failure. I'll take it for a spin and report back but it did get me nice and frustrated until I read this post. Thanks

 

Anytime you disconnect the battery, you'll get a PSM failure message until after your next drive. I doubt you have any issue.

 

If you have a CTek or similar maintainer this is the unplug procedure:

1 - Click the control button on the charger to turn it off from current charging mode. On a CTek charger this means that only a single LED is on and no operating/identifier LEDs are lit.

2 - Unplug maintainer from the wall.

3 - Unplug maintainer from car (cigarette outlet or battery).

Older maintainers without control buttons should be disconnected from the wall first.

If one disconnects a 12V maintainer (live) from the battery or cigarette adapter a current pulse may happen which may cause issues.

Connection procedure is also important:

1 - Plug maintainer to the car's cigarette outlet or battery.

2 - Plug maintainer to the wall.

3 - Click the control button on the charger to turn it on to appropriate charging mode.

Older maintainers without control buttons should be connected to the wall after being connected to car lighter outlet or battery.

 

Just in case it means anything, is it possible there was a house power failure? That would effectively turn off your battery maintainer, and it won't come back online again (if it's like mine) unless you poke the button again to put it back in maintenance mode from "off." If your car goes long enough after such an event and does not get driven (or the correct charge mode reset on the maintainer), it is possible the electronics in the car will eventually drain the battery (say, a couple of weeks). If it's partially drained, but you can still start it, you could get the PSM failure message until you drive it a little.

 

It does not appear that to be the OPs case, but it is an interesting scenario. Is your maintainer a CTek? I imagine that a CTek will do that if mains power fails.

 

OEM Porsche (same as CTek, but costs more).

 

Great advice. I had to disconnect the battery and found this thread very useful.

 

Must lead a charmed life. I have generic maintainers without switches. Leave them plugged into the wall all the time, insert/pull out cig lighter adapter without consideration of procedure as ADias outlines above. Do this both on the GTS (GT3 and RX-7 before) and wife's BMW. Have never had an issue in the 25+ years using them. (Do get new maintainers about every 5 years.)