Radio stays on when I turn the car off? - Toyota Nation Forum : Toyota Car and Truck Forums

TheShagg · 01-04-2011, 04:35 PM

I have a 98 camry, and it just started this behavior where the radio will stay on when the car is turned off. Any ideas on that? Opening the door of the car does not turn it off (but it DOES turn the headlights off, as it always did).

Other possible symptoms:

The dash clock all of a sudden is dark, permanently off.

The lights and heater blower motor tend to get brighter/speed up when the engine comes off idle speed, sort of like the alternator clicked on.

I recently completely drained my battery on accident. It was totally dead, no coming back. I tried jumping it, but that would not charge the battery at all. Replaced the battery and it now charges fine, no problems, but the lights are still kind of flickery, as mentioned above.

To me it sounds like the alternator is having some kind of problem (bad diodes?), but I'm not sure if that would cause the radio problem.

xpeed · 01-04-2011, 05:50 PM

What kind of battery did you change it to? Doesn't sound like the alternator. Does it turn on when you take the keys out?

Then again, when was the last time you changed the alternator and how many miles you have now?

***fenixus*** · 01-04-2011, 06:16 PM

I think you've got some relay or fuse problem or loose ground problem somewhere. Electricity tends to follow the path of least resistance, so if primary path is failing and secondary one is available then it will re-route the flow, sometimes causing weird things to happen.

check all fuses (both under hood and in cabin behind the coin tray) and maybe relays first, you may take a look at battery terminals/wires (make sure they are tight and clean) and check also wiring ground points (link below):
http://www.toyotanation.com/forum/sh....php?p=3230226

You can get the alternator tested for free at Autozone.

TheShagg · 01-04-2011, 07:05 PM

I put in the Autozone Duralast Gold battery. I'm pretty sure the battery isn't the problem, that wouldn't make much sense unless the voltage is wrong, which I will check.

I did have to put a new positive post clamp on, as my previous one corroded so thin that it broke when I loosened it. I will check that for any issues.

Ground strap sounds plausible, I will also check that out. I could probably check that with a jumper cable - if the radio turns off when I ground the block to the frame, I know what the problem is for sure!

Unfortunately I don't have a backup car at the moment (the gf's heater core decided to blow last month! grrr!) so taking the alternator in will have to wait. I will, however, do what I can with a multimeter.

Thanks for the ideas. If you come up with any more that don't require spending money, I am all ears

TheShagg · 01-04-2011, 07:07 PM

Quote:

Originally Posted by xpeed

Does it turn on when you take the keys out?

Then again, when was the last time you changed the alternator and how many miles you have now?

I think I can turn it off and on when the keys are out - the keys don't make any difference.

The alternator is probably original, 140k miles.

***fenixus*** · 01-04-2011, 07:51 PM

hmmm, maybe it's not an electrical issue after all? you say that keys make no difference, perhaps it the ignition cylinder not locking and allowing you to remove the key? not sure, just thinking out loud.

try searching this forum for "radio stays on" or something, i think someone else had this problem before.

Duralast Gold batteries are very good. I have one on wife's Solara, even after 4-5 years it seems a tad stronger than a few month old Autocraft Gold on other Solara.

xpeed · 01-05-2011, 03:00 AM

Hmm, it's not the alternator because if it was, you'd have trouble turning the engine on as well. It could be some old wiring that's not flowing the electricity well. Try to have a mechanic test out the relays and circuits. I think some mechanics have machines that can check electrical problems in cars.

TheShagg · 01-05-2011, 01:02 PM

Haven't gotten to look at it, but got some more info:

The radio turns off around 15 seconds after the car turns off (I haven't timed it, that number could be wrong). Also, yes, I can turn the radio on and off when the key is out of the ignition (and the ignition is the off position, not in the accessory position).

Hopefully I get some time tonight.

TheShagg · 01-05-2011, 01:14 PM

Quote:

Originally Posted by xpeed

Hmm, it's not the alternator because if it was, you'd have trouble turning the engine on as well.

My thought with the alternator was that maybe its "buggy" and somehow allows current to flow into the "only on when running" circuit from the battery, causing the radio to stay on.

I only suspect the alternator due to the weird fluctuations in my lights and heater when the engine revs (which could also be a wiring problem). Clearly it is still working to some degree because the battery stays charged.

TheShagg · 01-05-2011, 07:09 PM

Ah HA!

While I was playing with it today, I unplugged my 400W inverter from the auxilary cigarette lighter, and the radio turned off! (Car was off) Plugged it back in and the radio turned back on!

GopherT · 01-05-2011, 09:55 PM

The inverters have large capacitors in them. These capacitors act like batteries to smooth input voltage changes. Once you turn your car off (and I assume what ever appliances you have plugged into the inverter), you have a big "battery" on the far side of the ignition switch that keeps your radio and any other accessory powered until the capacitors run empty.

Also, the inverter may be drawing too much of a load for your alternator to keep up with at low engine speeds. That is why your lights get brighter and fan spins faster as you hit higher rpms.

You might be shortening the already long life of your alternator with that heavy load. Reduce the number and size of appliances plugged into your inverter. Also, it is not just the alternator that is suffering, you might be heating up some wires and melt your wiring harness too. Inverters over 10 amps input (120 watts output) are not meant to plug into cigarette lighters! Be careful or be stranded looking at a burning car.

TheShagg · 01-05-2011, 10:48 PM

Quote:

Originally Posted by GopherT

The inverters have large capacitors in them. These capacitors act like batteries to smooth input voltage changes. Once you turn your car off (and I assume what ever appliances you have plugged into the inverter), you have a big "battery" on the far side of the ignition switch that keeps your radio and any other accessory powered until the capacitors run empty.

I'd be a bit surprised if they have enough capacitance to run the radio for that long.. I will investigate with my multimeter this weekend.

Quote:

Also, the inverter may be drawing too much of a load for your alternator to keep up with at low engine speeds. That is why your lights get brighter and fan spins faster as you hit higher rpms.

You might be shortening the already long life of your alternator with that heavy load. Reduce the number and size of appliances plugged into your inverter. Also, it is not just the alternator that is suffering, you might be heating up some wires and melt your wiring harness too. Inverters over 10 amps input (120 watts output) are not meant to plug into cigarette lighters! Be careful or be stranded looking at a burning car.

Hrm, that may be the case, I was only running a small heating pad for my back, and not always. I am not sure how many watts it is, i would guess less than 50, nowhere near 400, but I may be wrong. I often just left the inverter plugged in with no loads connected, but now I won't be doing that any longer.