Johnny_B

Before you flame me for not doing a search I did one and did not come up with this exactly...

I have a trickle charger plugged into the cig lighter. It solved the problem of the battery weakening after a week or so of not driving the 993. However, my stereo head unit still looses all its settings and acts as if it is right out of the box. Again, it takes 3 to 5 days for this to occur.

Does anyone think wiring the trickle to the battery would solve this? I would rather not do this but will to avoid this PITA...TIA.

flyenby

I have my trickle charger wired to the battery, and have never had any problem with memory retention of the radio. Got a sears trickle charger, that can be unplugged from the battery quickly.

vjd3

That's very odd ... the radio loses the memory after a few days, but will work correctly before that?

The radio typically has two power sources, one is switched with the ignition (which is the main power source) and the second is hot all the time, that's for the memory. If you get those power leads reversed on the radio harness, the radio will turn on all the time, even if the ignition is off, and will never remember its settings. But I can't imagine you would lose enough juice out of the battery to clear that memory and still be able to start the car. Sounds like either a radio/fuse problem or it's incorrectly wired.

Vic
95 C4

Eric Holdaway

Sounds like the trickle charger is not keeping the voltage up to a point were the radio likes it, oooorrrrr, it could be that the drop in voltage when you start the engine is actually dropping the voltage low enough to drop the memory.

Is the radio Factory or aftermarket?

How old is the battery and how many times have you killed it? If it is a wet cell battery, once you have discharged it once, you may as well change it out. It is really important to keep the voltage up so that the battery is not damaged.

What you really need to do is get the car to someone that can figure out why your car has such a LARGE drain. There is NO way the car should kill the battery in a week. Either a light, radar dectector, alarm, or amplifeir is staying on and draining the battery. This is the real cause of your trouble. You must find out what is draining your battery.

Johnny_B

Eric - you bring up some good points...I did have about a dozen times where the motor barely cranked but it was never dead. I think you are right - something is draining it.

It is an aftermarket (Clarion) radio and I also have a amped sub woofer connected directly to the battery which is supposed to turn off automatically via an internal switch. I will disconnect that to see if it solves the issue.

Otherwise it is weird to me that the battery will crank the engine right up but not hold enough for radio settings??? I will also check the fuse.

David in LA

Just to clarify...a "trickly charger" or a "battery maintainer"? There is difference between the two. I use the Porsche battery maintainer and my stock CDR210 has never had a problem losing its memory settings.

alpina22

JohnnyB if you look at the amplifier, most have a light indicating when it's on. After turning the stereo off, this light should extinguish. If it doesn't, then the remote signal from the head unit to the amp is probably the culprit. In most cases, the remote signal is from a solid blue wire. It may just be a bad connection. Check the fuse in the amp. Remove it and see if you have enough battery power overnight to start the car.

Johnny_B

alpina22 - just checked it - sub has no light but it does have three wires for power: GND, REM, PWR. It seems the PWR is going right to the battery...What is REM I wonder?

Also it seems the sub is connected to the stereo's BASS wiring instead of the SW wiring. I will fix that but I do not see how it could cause the stereo to loose settings...fuses seem in tact and good. Maybe the headunit is defective?

Full Boost

Johhny B,

The REM - most likely stand sof remote.

This should be the wire that switches the AMP on when the head unit gets turned on.

The REM cable shoud run direclty to your head unit and be joined with an appropriate LV output - if its not an OEM head ( cause i have 0 experience with it) the REM or sometimes called the AUX cable comes from the head unit in usually GREEN or BLUE and can smoetimes be used to power an external antenna etc. (not sure if yours has one - mine doesnt)

IF the REM cable is direclty wired to the battery - it WILL DRAIN IT - Period.

let me know how it goes

Simon

Johnny_B

Thanks Simon - I will check the REM source in the morning. Can the REM be wired to any output from the head that sends a signal - like the SW or bass wires? On the sub I do see a 'AUTO POWER' switch w/two settings: ON or AUTO.

graham_mitchell

It would be very easy to check whether the radio loses power when the starter motor engages. Just check the radio immediately prior to and after engaging the starter. That should provide some answers.

Full Boost

Johnny,

Sorry for my typos...... The REM just needs to know WHEN the deck (or head unit) is switched on. This acts like a relay which thens turns the power from your battery on. So yes it can come from any source (labels include - REM, AUX, SW, ANT, and a host of others) as long as it tells the amp when to turn on.

As it is an aftermarket deck i would only assume that the wiring isnt correct and the PO or installer has the mem and pwr cables all confused.

Let me know how you go tomorrow

Simon

Johnny_B

Simon - Figured it out thanks to your help...

The sub had a switch for Power ON or Power AUTO. It was set to ON - changing it to AUTO I guess turned the sub off after a time out and thus the battery no longer drains.

THANKS SIMON FOR THE FIX!! CASE CLOSED...

Full Boost

Johhny,

Pleasure is all mine! Glad to be of assistance.

is this a great place or what????

Mike J

From my understanding is a "trickle charger" is a charger that charges the batter at a low current (amperage). The simpler trickle chargers do not have any intelligence and just keep on charging even if the battery is charged. A good battery maintainer idoes trickle charge the batter but should have the smart to detect when the battery needs a charge and applies it. Acid-Lead batteries have a natural internal resistance and self discharge, as well as the 993 draws a bit of current when parked. The battery maintainer will detect if the voltage of the battery drops and start a charge cycle. This allows the battery to cycle which keeps it fresh. A trickle charger, on the other hand, may just keep on charging that battery regardless of its charge state which is not good for the battery over the long term.

Then again I could be wrong... ;-)

Cheers,

Mike