UserA

Did a full respray in the summer on the 993C2S and since then the radio comes on seemingly whenever it wants when the car is parked. Very odd to hear the radio on at 3:00 AM while the car s sitting in my garage. It has drained the battery a couple times and I can't seem to find the issue.

Anyone have any ideas?

jansan946

A few questions:

1. Is the radio the original Becker unit from the factory?

2. Is the radio powering-up even though it's put into the "off" state using the radio switch before shutting down the car?

3. Did you remove and re-install the radio during the respray?

UserA

Answers

jansan946

This didn't start to happen on Halloween, did it?

OK, so you apparently have a factory-installed, Becker CR-210 radio in your dash. This radio has a push button "ON" switch in the upper left-hand corner of its faceplate. As you know, you can operate this radio with the ignition switch "off" and the key removed. You turn it on by depressing the radio's ON switch... so it's actually and on-off switch.

My best guess is that the radio's on-off switch is failing somehow with the symptom that it randomly turns itself on. I think you can confirm that if you happen to catch it playing away while parked. Just see if you can turn the radio off by depressing the faceplate's "ON" button. If it shuts off, you've found your gremlin.

You might be able to have the switch replaced locally or by sending the radio in to Becker Autosound (beckerautosound.com).

Please let us know how it turned out.

kjr914

I like jansan946's radio switch idea. As well, if radio kills the battery repeatably, you could just pull the radio out, disconnect it for a month or so and see if the issue is fully remedied. Its possible you have overlapping issues, or the radio is just a symptom.

I doubt the respray has anything to do with it....unless (long shot/SWAG alert)....did they disconnect the battery? Perhaps you have the failing ground strap that causes all sorts of weird issues. (Highly doubtful its the answer, but can't think of other connections to a paint job...)

deekay911

I had a similar problem, turned out to be the ignition switch. Even with the key off and out, the electrical switch at the back of the lock was allowing current through...enough to power the radio.

pp000830

I like the above idea especially since the switch can be replaced. Also a stuck relay that powers accessories may be the culprit. I would look over the relay list on the inside of the fuse/relay box in the frunk and see if a relay is noted as powering accessories or the radio. If yes it could be stuck in the closed position and needs replacement.

Just some educated guess work.

pp000830

Are you saying above that this is the standard operating function from the factory? My 86' Carrera would leave certain accessories working with the key out until a door was opened. My 96' with the original radio and later on with an aftermarket one tied into the same wiring harness cut-out with the ignition in the off position.

Radios have two hot wires. One that goes to the battery directly and one that goes through the ignition switch or a relay powered by the ignition switch. The ignition wire tells the radio if the ignition is on or off. In the off or unpowered position the absence of voltage on the wire shuts the radio off and usually the power to any power amp as well. To me the issue is that the relay in the radio is bad and sticks closed an external relay associated with the ignition is faulty, the ignition switch is faulty or some other source of positive voltage is present that is connected to the ignition wire.

Here is something that may help sort it out:

jansan946

Here's page 11 of my MY96 993's factory radio manual:




Now that my memory's refreshed, note that the radio is turned unconditionally "off" when the detachable display's removed. This appears to be an immediate and effective solution for the original poster's gremlin.

Of course, this assumes that the factory Becker radio is still in place.

BlackCar

I have the same problem in my 96. Here's my situation. Any advice graciously accepted.
Radio will turn-on intermittently while car is parked and battery drains even with radio off. Hi-Fi audio system is unmolested from new, so I expect hot wire and ign wire are not reversed. At rest 280 ma draw at battery, but with radio fuse out drops to 20ma. So I'm focusing on the radio, amp, ignition switch, or bad wiring....I think.

1. Replaced the original CDR210 with a good working CDR220. Problem persisted, so I said it's not the radio or the on/off button.

2. I can hear the solenoid on the Nokia amp under the pass seat click when the radio is turned on and off...so I hope that means it powers down when the radio is turned off.

3. No issues with the ignition switch. Car starts normally and key turns smoothly. But my next step is to replace the switch. Will take out the drivers seat this winter and snake myself under the dash to install a new switch.

4. Is there any way to test the antenna booster, or is that not something that will power on the radio or draw power at rest?

Right now I keep the battery on a trickle charger, so the car starts without drama.

flyingchappy

I had the same problem just a month ago with the ignition switch. It's not uncommon that the contact housing becomes slightly separated from the rotating points on the unit. Root cause is the ignition switch unit behind the tumbler block. The mechanics of the key tumbler are separate from the switch and only mechanically connected. Replace the switch itself. It's a PIA to remove and install but if you are contortionist or a member of Cirque du Soleil you'll have little issue.
Order this: 964.613.012.00.
PM me if you need advice.
Cheers,
Greg

pp000830

Would it be easier to drill out the security fasteners behind the key-way fascia disk and pull down the entire lock to get to the switch on the back of it?

I did this once on my 86' and it seems it was not too hard and offers the opportunity to clean re-lube the steering wheel lock deadbolt mechanism. I seem to recall I replaced the security fasteners with plain threaded screws to make a future removal easier.
Andy

flyingchappy

That would work and certainly an option. I decided not to drill. Removing the drivers seat is a big help.

becker - 97'C4S

I started getting the issue about 6 months ago I'm original owner with original radio...actually it just did it as I write this ... people here say maybe the ignition contacts and some other say the ground of the radio is touching the car's and is not supposed to.
That second option I will check ... I was making sure the radio is off before turning the car off and had the volume down but since lately it was fine of course I forgot went for a spin a couple of days ago all good and now I can hear the battery doesn't have
enough juice to unlock the door I hear a weak try. The car is locked so manually is supposed to work by taking off the plastic cover on door lock...BTW somebody was saying there is an emergency hood unlock thingy you access on the wells of the drivers side since
I hear some are afraid to jump the car...I had jumped multiple times no issues, also I'm out town avery other 3 months so I just unplug the battery and plug it back and it has always fired up. Anyway some extra FYIs for anyone with the same issues.

geolab

The rectangular Bracket - jacket - whatever it is called , that is fixed on the dashboard, and the radio slides in it, must never touch the metal core of the dashboard.
The original units installed in 993's or units certified after 1998 , are Polarity Positive Always, for the alarm signal green cable behind
If the braket touches the dashboard metal, it grounds the radio chassis turning it on.
to test, slide out the radio an inch without unplugging the electrics, and with a nuded end piece of wire , put one end on the radio chassis, and the other end touch any metal ground , and your radio will turn on by itself
This concerns original mount at least