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"SYS" flashing in digital speedo window


Well-known member
Nov 22, 2001
colton, oregon, usa
'93 Black 6 Speed
When driving home from work I noticed inside the digitial speedometer window the word "SYS" was flashing 3 times about every 10-15 seconds or so. It would turn off any gauge or fuel information and replace it with "SYS". After making a stop at a store and then returning to the road, it never did it again. Seems that turning the engine off and restarting cleared the problem up. The only thing I'm currently having a problem with is a week battery. The other day it didn't have enough juice to turn it over, but after letting it sit for a bit it did fire off. And then this evening I actually had to get a jump to get it going after making a second stop at another store. However, still no repeat of this "SYS" flashing. Anyone know what the "SYS" is ? I suppose it could be something with the battery, but I'm not sure how - as the alternator is showing 14+ volt output by the gauges. The battery is dated 1997 - so I'm sure it has a bad cell in it, I'm going to pick up a new one tomorrow. Any thoughts on the "SYS" ????


If you let a battery go too far dead and try to recover the charge with your alternator alone, and not charging the battery first with a charger, you stand a good chance of shortening the lifespan of the alternator. The alternator may not be supplying enough juice to keep the battery charged and all of the systems functioning properly at the same time, therefore the "SYS" light flickering.

I hope this helps you.

SYS decode

To read the CCM
Key Off
Have pen & paper ready
Jump pins a & g in tha ALDL connector
(Top left A bottom right G)
turn key on
This will start the Auto diag of the CCM
The numbers where the speedo lives will give you codes
eg C 51 or H 51
(the C means current H means History)
and below there will be another number
( eg 1.1, 2.1 etc)
These will tell you the MODULE at fault.

To exit
Key off
remove the jumper
Write this info down
I'll get my book
and away we go.

Picking up a new battery this afternoon, so hopefully I won't see the error again, or harm the alternator....But I am interested in checking out the error code. Where is the ALDL connector ? Everything else sounds easy enough - once I find this connector. What does the ALDL stand for ? I would assume 'diagnostics' is the D ?
The Assembly Line Data (or Diagnostic) Link is located near your right knee. ;)

_ken :w
Read the codes

It wil give you a better idea of how things are preforming.

The H(istory) codes are good for intermittants.

The C(urrent) is where your at now.

It will take all of two minutes ( maybe 3 if you write slow)

A couple things, as I have been down this road...

First, replacing the battery is harder than it sounds, and takes a bit of time.

Second, yes a toasted battery will cause the "sys" to flash. Mine did. I had a bad cell in the battery, so occasionally/randomly, the "sys" would flash. The dealer tried to figure it out (pulled the codes) and found nothing. They wanted to replace the dash assembly.

Best of luck.
Well, new battery is in - no problem, piece of cake. There must be some difference in '92, the '93 is pretty straight forward. I will attempt to get the codes out of it to see what it says, but I think it was the dead cell in the battery that was tripping it up. Funny thing is the CD player played perfectly this morning - it usually has background 'static' in it. - fixing the sterio is a project i haven't dove into yet. But anyhow, I wonder if the battery somehow was messing up the radio ???

So the stereo NOW has static with the new battery?

CD only or all modes?
C'mon Mike, open your eyes! :L

"Funny thing is the CD player played perfectly this morning - it usually has background 'static' in it."

_ken ;)
Early post
"Picking up a new battery this afternoon"

Next post
Well, new battery is in - no problem,

Last post
Funny thing is the CD player played perfectly this morning


( doing the Homer Simpson doughnut drool still )

Must have C-2
MMmmmmmmm convertible

As some of the more astute members have pointed out the CD has cleared up since putting the new battery in...:)

As to the other modes, the radio still kind of 'comes and goes'. It works all the time but goes in and out of 'tune' so to speak. It sounds like it is getting poor reception and fading in and out of stereo - but it is actually getting good reception, something internally is causing it. However, the radio did seem to make some improvement - not fading in and out as bad as it has been. Now the real strange part is, the cassette player has worked (sounded) perfect all along. I have printed out all the info on how to remove the various stereo pieces from the tech section here, but am wondering how many pieces of it really need to be pulled out and repaired. Any Bose experts here that have seen these circumstances ? suggestions ??

Still haven't got the codes, work has kept me after hours lately...Going to try to go through that procedure this weekend.

Thanks for all the feedback input and questions guys (and gals).


Er um ( what does astute mean?)

The "Noise" was from the ALT putting out a heavy charge... Alot of ripple coming down the power buss!

The radio drifting in & out... the "Radio" is not in the head unit in the dash . but it is a little silver box in the right rear floor hatch behind pass seat.

You might want to disconnect the battery, remove the unit clean & reseat the connectors.

In addition check the antenna connection point at the rear of the passenger compartment where the antenna connects through the bulkhead connnector.

Clean the antenna as well, there is a mechanical connection internal of the mast, if the antenna is all grimy.. that will be poor too!

If it's still funky...you need to replace the silver box.

Hey, great info on the radio problems ! Thanks vigman.

I put a new antenna mast on about a month ago, so it is in good shape. And it didn't change the radio performance. (the antena was just broken right at the top) . I will check out the connectors on the silver box - at least it is easy to get too.

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