S10 Blazer's radio & clock lose engine-off power

mbient

When the vehicle sits for several days, the radio's digital clock loses time and the radio doesn't work until the engine has been running for 5-10 minutes. Battery is new.

I'm thinking there could be an auxilary power capacitor in the radio circuit that is failing, losing its charge very quickly when the engine is turned off, and then slowly recharging when the engine is started.

If this is the problem, does anyone know where that capacitor is located?

If it's not a capacitor, any ideas on the problem and a fix?

duntov

I don't know what difference it would make wheather the ignition is in the run accessory or off position to make the clock lose time. The clock has battery power in all positions of the ignition switch. The radio has battery power only with the ignition switch in the run position or in the accessory position.

I do know this, if modern cars with electronic components such as a digitial clock, sensors, relays, remote door locks, alarms, moduiles, ECM, etc., are not driven for an extended periods of time the battey can run down due to parasitic battery drain. Some vehicles have as much as 50 ma battery drain. For example, an intermitten short in my power door lock relay drained my battery to zero volts after the car had not been driven in four days. I replaced the battery and the relay failed completely and the power door locks would not function. Then I replaced the relay and the door locks worked perfectly. I suspect the old battery was quite weak to start with and did not take much of a short to drain it. It is probably not necessary with a new or good battery but I installed a Deltran Battery Tender and I keep it connected to the battery when I know the vehicle is not going to be used for an extended period.. A battery "trickle charger" such at that type, keeps the battery at full 12V at all times, just as if the car is being driven and the alternator is charging the battery.

You may have a short or bad contacts in the ignition switch.

mbient

Worn ignition switch contacts is an interesting thought, I'll certainly check that out. Thanks

I know it's not the new battery, strong crank and starts right away.

Still think it could be a marginal electrical power storing component that is going bad. Clock and radio work fine when the engine is running and power is being generated by the alternator.

Should add that on some occasions, the radio has sever static at first, then, as time passes (capacitor gets charged and full power gets through?), the static stops and the sound is loud and clear as ever. This is on a local station with a strong signal.

rfletcher

S 10 Blazer, 4.3L, 185000 miles, excellent condition.. Five days ago, while driving at 65 mph, the engine suddenly quit. Tach. zero, oil pressure zero, check engine light came on. I coasted approx. 1/4 mile looking for a safe place to stop. While coasting I I shifted to neutral and tried the starter. On second attempt the engine started. Everything looked normal. About two miles further, same thing happened and again I was able to restart without stopping. This occurred three more times, over about 20 miles, before I arrived home. I have driven several short trips over the past five days without a problem. For what it's worth, about one year ago it died while driving but would not restart. Defective oil pressure switch shut off the fuel pump. Replaced sensor with a NAPA unit. No problem since. Also noticed another odd thing. The clock was several hours off. The check engine light only comes on when the ign. is on and engine off. There are no OBD codes stored.

Any one have a thought as to what might be happening ?

Thanks

rfletcher

S 10 Blazer, 4.3L, 185000 miles, excellent condition.. Five days ago, while driving at 65 mph, the engine suddenly quit. Tach. zero, oil pressure zero, check engine light came on. I coasted approx. 1/4 mile looking for a safe place to stop. While coasting I I shifted to neutral and tried the starter. On second attempt the engine started. Everything looked normal. About two miles further, same thing happened and again I was able to restart without stopping. This occurred three more times, over about 20 miles, before I arrived home. I have driven several short trips over the past five days without a problem. For what it's worth, about one year ago it died while driving but would not restart. Defective oil pressure switch shut off the fuel pump. Replaced sensor with a NAPA unit. No problem since. Also noticed another odd thing. The clock was several hours off. The check engine light only comes on when the ign. is on and engine off. There are no OBD codes stored.

Any one have a thought as to what might be happening ?

Thanks

chevyride22

Message:
I have a 1995 Chevy Blazer S-10, 6 cylinder, 4WD. After the engine warms up and you are driving down the road, the engine completely cuts out. If you let it cool off for about 10-15 minutes, it will start again, but you get a hesitation for awhile(almost like it is out of gas) and then it cuts out again. This just recenly started happening. The fuel pump and fuel filter were replaced in January 2009 along with plugs and wires. The problem seems to be temperature related (everytime the engine cools down the car starts again). Any suggestions as to what might be causing the shutdown? Thanks.

chevyride22

I have a 1995 Chevy Blazer S-10, 4WD, 6 cylinder. I am getting trouble code P1406 manufacturer specific powertrain trouble code.
The other pending trouble codes are P1100 manufacturer specific powertrain trouble code and P0700 transmission control system malfunction. What can I do to
resolve these codes? Will pending trouble codes clear automatically when the problems are resolved? Right now when I clear the regular trouble code, it clears, but the pending ones stay. Thanks.

tidester

You'll probably want to post your question in the Chevrolet Blazer Engine and Performance Problems discussion.

tidester, host
SUVs and Smart Shopper

kaiserscorner

Trying checking the crank sensor. Ive had a couple of vehicles (Jeep Cherokee and a Volvo) that have had this problem (run for about 10 - 15 minutes then shut down and restart after cooling) and in both cases I replaced the "Crank positioning sensor" and both vehicles were like brand new! Hope this helps, I'm not a mechanic!