Unoffical empeg BBS

Quick Links: Empeg FAQ | RioCar.Org | Hijack | BigDisk Builder | jEmplode | emphatic
Repairs: Repairs

Topic Options
#95457 - 23/05/2002 09:15 freezes when braking
alaskan7
new poster

Registered: 08/01/2002
Posts: 9
Loc: Anchorage, Alaska
I had my empeg installed a week ago, the installer ran into a problem that when the brakes were applied the empeg would go blank and music would stop for a few seconds. He supposedly got that fixed, however it still happens frequently, not all the time like before.

The battery icon appears, which in the FAQ indicates the unit is getting 10-11 volts. It doesn't matter if my lights, A/C, or any other accessories are on or not however, the only time it will cut out is just when the brakes are applied, and always for two or three seconds.

Before I go into the dash myself I wanted to see if anyone had a similar experience or thinks drawing power from a different source would fix this.

Top
#95458 - 23/05/2002 09:21 Re: freezes when braking [Re: alaskan7]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31602
Loc: Seattle, WA
Sounds like something is miswired to me. What kind of a car is it?
_________________________
Tony Fabris

Top
#95459 - 23/05/2002 10:53 Re: freezes when braking [Re: alaskan7]
thinfourth2
Pooh-Bah

Registered: 13/04/2001
Posts: 1742
Loc: The land of the pale blue peop...
Have you tryed measuring the voltage in the car wth the brakes on you might have a short on the brake light circuit but i would expect that to blow a fuse.
_________________________
P.Allison fixer of big engines Mk2+Mk2a signed by God / Hacked by the Lord Aberdeen Scotland

Top
#95460 - 23/05/2002 15:06 Re: freezes when braking [Re: tfabris]
alaskan7
new poster

Registered: 08/01/2002
Posts: 9
Loc: Anchorage, Alaska
It's a 93 RX-7

I think something's miswired too, since my tuner doesn't work, unless I don't have the tuner software installed correctly. When I press the tuner button I get the "play" icon, I'm not able to see if the tuner LED is lit

Top
#95461 - 23/05/2002 15:54 Re: freezes when braking [Re: alaskan7]
Shonky
pooh-bah

Registered: 12/01/2002
Posts: 2009
Loc: Brisbane, Australia
Is this with the engine running? Also you don't say whether this happens when you turn on the accessories like AC etc.

When you apply the brakes (or any large load particularly with the engine off) there is low going transient on the voltage line due to the brake lights which draw a fair current. With the engine off in my car pressing the brakes will generally cause the empeg to shutdown and restart due to a low voltage. With the engine running there's no problem though. The empeg seems very sensitive to these transients and seems to decide the power is low. Initially it only blanks the screen and turns off the amps so it doesn't actually reboot. It only reboots when the 3.3v supply drops out and the reset chip forces the processor to reboot.

Does it do it when you turn your head lights on? They should cause an even larger transient.

I remember someone talking about a largish (1000uF comes to mind) capacitor connected right near the empeg to filter out these transients. Did a quick search and couldn't find the post - perhaps I made it up.

I'd be checking your power wiring and if possible temporarily wire it straight to the battery terminals.
_________________________
Christian
#40104192 120Gb (no longer in my E36 M3, won't fit the E46 M3)

Top
#95462 - 23/05/2002 16:41 Re: freezes when braking [Re: alaskan7]
AndrewT
old hand

Registered: 16/02/2002
Posts: 867
Loc: Oxford, UK
Perhaps it's poor grounding to the Empeg as opposed to something drawing excessive current?

During the fault condition a bad ground could float above real chassis ground. Since (from the Empeg's perspective) it's supply voltage is the difference between the +12v feed & it's ground connection this could be a cause.

If you have a Voltmeter you can test this by measuring between *real* chassis and the *actual* Empeg ground connection while the fault condition exists. If you get a reading above (e.g.) 0.5v then this could be the cause.

Alternatively you could just skip the voltmeter part and run temporarily a big fat cable across the bonnet (or the hood if you have one of those instead ) straight to the chassis earth near the battery for testing purposes.

Top
#95463 - 27/05/2002 00:58 Re: freezes when braking [Re: AndrewT]
exrpilot
new poster

Registered: 08/04/2002
Posts: 9
Loc: Nashville, TN USA
Mine does this also. I've double checked everything. I've tried different ground locations. I've tried conecting directly to the batery. When I mesure the voltage, I get 12.6v and when I step on the brakes it only goes down to 12.3v. Heck the voltage drops down lower when I hit the headlights and has no effect on the player. The power windows are the same deal. The voltage drops when the windows are raised and lowerd, and still has no effect on the player. My last resort may be using a big cap next to the unit.
_________________________
30 Gig #010101805 No other mods....yet.

Top
#95464 - 27/05/2002 12:10 Re: freezes when braking [Re: exrpilot]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31602
Loc: Seattle, WA
Question. Does the problem happen:

a) Only when the car is actually moving and you press on the brakes and the car is actually slowing down.

b) Even when the car is parked, when the brake pedal is pressed.

If (a) then it's a loose wire or connection somewhere that's affected by the G-loading from the braking manuever. If (b) then it's likely something to do with the wiring related to the lights, for instance, something like the headlight-sense wire from your car connected to the wrong wire on the empeg. Or perhaps a wire tangled up in the mechanism of the brake pedal assembly that's getting tugged, squished, or grounded.

Or maybe the wire running to the player is just too thin and you need to run a proper one instead of using the thin one from the car's harness.
_________________________
Tony Fabris

Top
#95465 - 06/06/2002 17:41 Re: freezes when braking [Re: tfabris]
alaskan7
new poster

Registered: 08/01/2002
Posts: 9
Loc: Anchorage, Alaska
for me it WAS both a and b

when I finally had time to troubleshoot I popped the hood and immediately saw the problem - the install shop had either failed to re-attach the negative to the battery post or had attached it loose so it came completely off. It was resting up against the post so the car would start, however whenever certain changes to the electrical system occurred, such as when the brake lights were on or when the cooling fans turned on, the empeg would go blank for a few seconds

now I can properly get back to drifting opposite lock around corners while heel and toeing, hitting the AC, and flashing the high beams without fear that the Initial D soundtrack will skip :P

Top
#95466 - 06/06/2002 22:22 Re: freezes when braking [Re: alaskan7]
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5549
Loc: Ajijic, Mexico
failed to re-attach the negative to the battery post or had attached it loose so it came completely off.

You are one lucky dude -- by all rights you should have fried your alternator running with the battery [intermittantly] out of the circuit!

tanstaafl.
_________________________
"There Ain't No Such Thing As A Free Lunch"

Top