Here's one for all the electronic gurus!
yankeeintruder
11-28-2004, 12:55 PM
Bought a 2001 Silverado 1500 in Oct. 2000. Hated the stock stereo so I installed a pretty nice system 1 month later. The head unit I installed never kept correct time....... was fast........ but I lived with it. It is a high end Eclipse unit, #55040. Dealer I bought it from said he'd send it back but I never did.
Fast forward to Oct. 2004, 3 years later......... the bulbs that illuminate the four buttons on the temp. control panel have burned out. You guys know this is a common problem........ (outside air, air circulation, ac and rear window defogger/heated mirrors buttons). Anyways, I decided to change the bulbs instead of buying a new control panel. I desoldered the old ones, removed and installed four blue LEDs with resistors.
NOW................ ever since that day............. my head unit keeps perfect time! And that was the only change I did. Didn't unhook the battery... didn't pull any fuses or nothing. I had the control unit out and unhooked several times to scope the job out.......... clock wasn't right until after changing the bulbs out. After 3 years of inaccurate time!
Only thing I can guess is there is too much voltage for the stock bulbs (or they are under rated) and somehow this circuit is tied in with the stereo set up. Installing resistors with the LEDs might have evened things out(????). But that just doesn't sound right.
Anyone have a theory of their own or maybe experienced something like this?? Oh....... by the way...... the stock head unit, as bad as it was, kept perfect time.
Fast forward to Oct. 2004, 3 years later......... the bulbs that illuminate the four buttons on the temp. control panel have burned out. You guys know this is a common problem........ (outside air, air circulation, ac and rear window defogger/heated mirrors buttons). Anyways, I decided to change the bulbs instead of buying a new control panel. I desoldered the old ones, removed and installed four blue LEDs with resistors.
NOW................ ever since that day............. my head unit keeps perfect time! And that was the only change I did. Didn't unhook the battery... didn't pull any fuses or nothing. I had the control unit out and unhooked several times to scope the job out.......... clock wasn't right until after changing the bulbs out. After 3 years of inaccurate time!
Only thing I can guess is there is too much voltage for the stock bulbs (or they are under rated) and somehow this circuit is tied in with the stereo set up. Installing resistors with the LEDs might have evened things out(????). But that just doesn't sound right.
Anyone have a theory of their own or maybe experienced something like this?? Oh....... by the way...... the stock head unit, as bad as it was, kept perfect time.
skipr
11-28-2004, 01:06 PM
Thats a good one! I have another riddle.. I turn on my a/c and cruise control engages.
gremlin96
11-28-2004, 07:27 PM
Thats a good one! I have another riddle.. I turn on my a/c and cruise control engages.
bad ground or short in the system. you will need the scatmatic in order to see ware the syetems meet.
the hole clock deal is realy easy. i bet if thay had not burnt out and you put a scope to check the voltage you would of seen a riple on the dc input. this will speed or slow down the clock depending on how the ripple is set up. rember the clock only tells time by a xtal.
bad ground or short in the system. you will need the scatmatic in order to see ware the syetems meet.
the hole clock deal is realy easy. i bet if thay had not burnt out and you put a scope to check the voltage you would of seen a riple on the dc input. this will speed or slow down the clock depending on how the ripple is set up. rember the clock only tells time by a xtal.
yankeeintruder
11-28-2004, 09:52 PM
Thanks for your input gremlin........... so you think the ac/temp/fan control module is somehow tied in with the stereo set up?? Wondering why then it didn't affect the stock head unit..... and why the ripple isn't there after replacing the burnt out bulbs??
And sorry, but I don't understand what you mean when you say "the clock only tells time by an xtal"??
And sorry, but I don't understand what you mean when you say "the clock only tells time by an xtal"??
nineball481
11-28-2004, 10:16 PM
a crystal is used in electronic clocks, as opposed to gears and springs
gschretter
11-28-2004, 10:45 PM
Skipr you crack me up !!
Had a 72 Datsun that if you hit the left signal the brights would come on only on the right side and all the other head lights would go off.
Clock being off:
Wonder if you spliced into an line that was also being used for the lights and there was some kind of ground problem.
The reason is maybe your lights might have burned out is from to much drain / volts being forced to be drawn from the radio.
If you supply more than 13.5 volts to any electronic item that is rated for 12 volts it will seem to make the item run faster but burns out very fast.
Had a 72 Datsun that if you hit the left signal the brights would come on only on the right side and all the other head lights would go off.
Clock being off:
Wonder if you spliced into an line that was also being used for the lights and there was some kind of ground problem.
The reason is maybe your lights might have burned out is from to much drain / volts being forced to be drawn from the radio.
If you supply more than 13.5 volts to any electronic item that is rated for 12 volts it will seem to make the item run faster but burns out very fast.
yankeeintruder
11-28-2004, 10:58 PM
Nope........ no splicing done. Used a harness and tied directly into the factory stereo harness. I'm also thinking the wiring for the ac control pod and the stereo are tied together somewhere.
buttnekked
11-29-2004, 11:37 AM
the illumination circuit is the most prevalent common factor. The ripple in the current could have been an issue for the eclipse and not the oem because of differences in the tolerance and and accuracy of the circuits. Presumably the eclipse circuitry would be much cleaner and have less voltage drop than a typical oem unit.
gremlin96
11-30-2004, 07:56 PM
Nope........ no splicing done. Used a harness and tied directly into the factory stereo harness. I'm also thinking the wiring for the ac control pod and the stereo are tied together somewhere.
yes all the grounds are most likely thru the same point. also the illumination circuit and its gound run thur the head light switch. when you turn up or down the lights for the dash every light on the dash execpt the air bag light dims.
yes all the grounds are most likely thru the same point. also the illumination circuit and its gound run thur the head light switch. when you turn up or down the lights for the dash every light on the dash execpt the air bag light dims.
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