Weird electrical issue, anyone have any ideas?

[dma550]

Hey guys

Late last week, I found my battery dead when I came out to the car at the end of the day. I suspected my own stupidity, coupled with the fact that the car is a garage queen and can sit for a week+ in between drives.

I called AAA and they tried to jump with a portable battery box, which would not start the car. They jumped it and it started, I drove home.

I noticed my dash lights weren't on, but all indicators work. I tried the dimmer adjust and it would not brighten them. I then noticed that the second light switch in the control stack seemed to do nothing. I now know I have no tail lights either.

I checked all of the fuses in the cabin and adjacent to the brain, all look fine. Does anyone know what could be the issue?

This is a bummer as HRM has closed, I don't have any local support. The car is now sitting disconnected from the battery as I read an electrical reset can help this.

Anyone have any ideas or troubleshooting steps? Battery is fine, car runs. Thanks

[Randy Chase]

How do you know the battery is fine?

[dma550]

Thanks Randy

It starts the car, Headlights, stereo, signal lights, etc. No tail lights, no front marker lights. I would think +12V enough to start would be enough to power some misc. electricals. I used to be able to turn on the parking lights, the switch does not do that anymore

[TheViper]

Did you check the fuses under the front access panel, specifically fuse F16?

[CALtd]

Originally Posted by TheViper

Did you check the fuses under the front access panel?

Is this under the theory that the jumping process spiked or otherwise blew some fuses?

[Randy Chase]

Good catch. In the cabin and adjacent to the brain is not the main fuses you need to check.

[TheViper]

Check fuse F16

[dma550]

It was the first 20A fuse under the front access panel. Very odd, thanks all. So now, only time will determine if the fuse blew from the jump start or if the fuse blew causing me to NEED the jump start!

[knucklehead]

This may be a dumb question, but I went on the Sunday drive this weekend. While coming home my radio started acting weird. Lights on but no sound. Then my turn signals stopped working. A few miles later a CEL lit up. Is this all coincidental or are these all related. Checking the fuses today, but can a blown fuse give you a CEL?

[TheViper]

Interesting, because that #1, 20A fuse is only for the power outlet

Originally Posted by dma550

It was the first 20A fuse under the front access panel. Very odd, thanks all. So now, only time will determine if the fuse blew from the jump start or if the fuse blew causing me to NEED the jump start!

[apk919]

Originally Posted by knucklehead

This may be a dumb question, but I went on the Sunday drive this weekend. While coming home my radio started acting weird. Lights on but no sound. Then my turn signals stopped working. A few miles later a CEL lit up. Is this all coincidental or are these all related. Checking the fuses today, but can a blown fuse give you a CEL?

The radio symptom is consistent with low voltage... I've had that happen if I leave the stereo on while I work on the car... and I eventually discharge the battery (I have a Braille, so it doesn't take long to discharge).

There is a CEL for low system voltage: P0562, so that might be the code you're throwing... do you have a voltmeter handy to check your system voltage (both with the engine on and off)?

[charliex]

yeah a blown fuse can give you a MIL, i forget which fuse it is off hand but one of the ones in the two engine bay packs will cause some problems with the lift and subsesquently set codes, it might be ecu b+ but that usually limits the rpm too.


dma, was the portable battery box the cigarette lighter type ?

[knucklehead]

Originally Posted by apk919

The radio symptom is consistent with low voltage... I've had that happen if I leave the stereo on while I work on the car... and I eventually discharge the battery (I have a Braille, so it doesn't take long to discharge).

There is a CEL for low system voltage: P0562, so that might be the code you're throwing... do you have a voltmeter handy to check your system voltage (both with the engine on and off)?

Originally Posted by charliex

yeah a blown fuse can give you a MIL, i forget which fuse it is off hand but one of the ones in the two engine bay packs will cause some problems with the lift and subsesquently set codes, it might be ecu b+ but that usually limits the rpm too.

dma, was the portable battery box the cigarette lighter type ?

The car had been running for most of the morning. Wouldn't the alternator recharge the battery? I'll see if I can borrow a voltage meter and a code reader. Thanks guys for the help.

[reggiem]

Originally Posted by knucklehead

This may be a dumb question, but I went on the Sunday drive this weekend. While coming home my radio started acting weird. Lights on but no sound. Then my turn signals stopped working. A few miles later a CEL lit up. Is this all coincidental or are these all related. Checking the fuses today, but can a blown fuse give you a CEL?

I got a CEL at the track last weekend and it was a blown fuse. However, I was also limited to 6,000 RPM in addition to the CEL. In my case it was the R4 fuse (first fusebox next to the ECU, and the farthest forward if I remember correctly).

[apk919]

Originally Posted by knucklehead

The car had been running for most of the morning. Wouldn't the alternator recharge the battery? I'll see if I can borrow a voltage meter and a code reader. Thanks guys for the help.

I just took a look at the schematics, and it looks as though the hazard/directional flasher is the type that needs a minimum load current to work properly... which also means that below a certain system voltage your directionals won't work either.

That's two symptoms that indicate low system voltage, at least at the instrument cluster. It's possible you have a loose connection somewhere that's causing the voltage downstream of the alternator to be too low.

EDIT: Do the turn signals come on, but not blink?

EDIT 2: On reviewing the schematic, the hazard/flasher unit does not look to be load sensitive... but might be voltage sensitive anyway...

[knucklehead]

Originally Posted by apk919

I just took a look at the schematics, and it looks as though the hazard/directional flasher is the type that needs a minimum load current to work properly... which also means that below a certain system voltage your directionals won't work either.

That's two symptoms that indicate low system voltage, at least at the instrument cluster. It's possible you have a loose connection somewhere that's causing the voltage downstream of the alternator to be too low.

EDIT: Do the turn signals come on, but not blink?

Nope, I got naddah. Any recommendations on where to start checking connections?

[apk919]

Originally Posted by knucklehead

Nope, I got naddah. Any recommendations on where to start checking connections?

The turn signals don't come on at all? Or don't blink? How about when you press the hazard switch?

EDIT: Power gets to the flasher module differently under those two circumstances, so that might be a good debugging step...

I'm assuming that your doors lock and unlock properly and the interior light comes on when you open the door?

[knucklehead]

Originally Posted by apk919

The turn signals don't come on at all? Or don't blink? How about when you press the hazard switch?

EDIT: Power gets to the flasher module differently under those two circumstances, so that might be a good debugging step...

I'm assuming that your doors lock and unlock properly and the interior light comes on when you open the door?

I'll go check. I lock the doors using the key. be back in a few.

[TheViper]

I am betting you have a high resistance connection somewhere. Check all connections at the battery.

[knucklehead]

OK...

Signals - nothing
Hazard - one blink when I press the button then nothing
Locks - work, both from the fob and the button on center console.
Inside cabin light - working

Checked the battery cable and it seems tight. Could it be the cable themselves? I have had the battery die for no reason twice. And there is a current draw that I've never figured out, but as I said before I don't know why the alternator doesn't seem to recharge the battery well.