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Error Message Panic and next steps


Supporting Member
Hi helpful folks out there in the community...have been enjoying my little blue baby... did a couple of long trips and maybe after range charging seemed to have a bit longer range for a bit, then it seems to have drifted down but still reasonable. Loving driving this car.

BUT THEN day before yesterday had a shortish drive (40 miles) still had like 120 miles ideal range left, came home, plugged her in, the next morning when I unplugged and was going to run out to store, I had an error message:
"SWP: APS off, but no pulse from BPS" (code 420). So I had absolute newbie panic, went straight to this site. Didn't find much on this site or by google search, so went out and plugged in thinking maybe I should try storage or another charge mode. Went back to computer and found out some translation for the alphabet soup: "BPS backup power supply, SWP switchpack, APS auxiliary power supply".

Okay, now I am really panicking, that error sounds very serious...found the one thread were a similar message (and others) on a wreck was basis for like a complete over hall...so I go out to check on car, and talk to her in her pain (and my panic), and bring 2gb flash drive to download vehicle log. Do that (have to unplug) and " say, okay maybe if a do a range charge it will reset". So while I head inside to try to do the parsing translation and graphical parser, she (my blue baby) is on range charge. SO I read the tar in csv and graphics and (OH NO) at the very bottom it has "sync fail" and data stopped on the download on AUg 15 (its now sep 9). So don't have any seemingly helpful data. (and no, I have been researching but haven't done OVMS yet).

So I go out to try to sync and download the log files again (full of self doubt, did I pull before the sync was finished?) and THE ERROR MESSAGE IS GONE. We have charged, driven a bit, replugged and charged and driven a bit and error message hasn't returned.

ALAS the log file however on 2 more attempts is still not syncing/finding data after Aug 15. "sync fail"

ANy suggestions what to do at this point and what it all means?

PS cause its on another thread, this blue baby is #412, Roadster 1.5, original battery, got with 9000 miles, range was like 180, though variable, sometimes 165, went up to ideal 189 after one of the range charge experiments (with range mileage of like 220 or something) then has been drifting down back to like mid 160's.

CAC from aug 15 was 141 by graphical parser,
Oh the wonderful world of Roadster (un)predictability :confused:

For the logs, perhaps it's something as simple as a bad thumb drive? Do you have another you can try?

For the error, this post seems to suggest Error #420 is related to the Service Disconnect:

Error ID is 420. It shows up everytime, you take out the Service disconnect and insert it again. The error disappears, when you restart the APS in the service menu.

Might also be your 400V controller but I'll leave it to the real experts on here to chime in.

Ideal Range variance is normal based on your driving. Nothing abnormal there IMHO.
Oh Thank you....the ID 420 error disappeared and hasn't recurred yet (so with my newbie threshold exceeded will hold off on taking out anything....until it reappears anyway!...along those lines for that potentiality... ahh....hope you don't mind another newbie question..what is/where is//.the service disconnect ...it is what exactly? I found this post...Service Disconnect but that sounds like a different area....

The log file thing I don't think is a bad thumb drive, I reformated it and the same cut point occurred. I actually do have data it turns out for some of the download through the time of the log (for example it shows the 420 error, and that it disappeared...but is missing stuff line the charge 2 data after Aug 15), but it cuts off at the same point (line 245615 as you can see in screenshot) every time (this is the csv output from the parser tool from : Logparse version _v18 08/03/2011, Copyright (c) Scott Swazey 2010,2011 ) (hopefully that is sufficient acknowledgment for the amazing work he and others have done for the whole VehicleLogs thing.)

snip of parsed file.JPG
oh, yeah I also agree with your comment re variance which I take to mean "driving habits"....I could feign being affronted by the "variance" comment...was someone implying I have a lead foot perhaps? little ol' me???? (sorry I-280 is just made for passing by cars with a little lead in the foot hehehehe vroom vroom there is a reason my prius never got the mileage my hubbies did :) ;)

(I so LOVE my blue baby:cool:)