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My 87 fleetwood brougham has an electrical problem. I have a new alternator and battery belt tension is good and its dead every morning and now wont take a jump. HELP!! WHERE DO I START LOOKING FOR THIS GLITCH??!!!
 

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94 FWB, 93 SDV, 94 FWB (sold), 90 Brougham (sold)
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Start by checking the battery. If the battery is bad it won't hold a charge. Check the power and ground cables. Engine to battery ground especially, it corrodes over time.
 

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94 Fleetwood Brougham
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Look for aftermarket stereo's, power antennas stuck on, trunk lights stuck on, hood light stuck on, bad alternator (remove red battery lead on alternator (not connector) to isolate, also look for it to be warm overnight), bad ignition switch.
 

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1995 ETC, 75 Deville, Cad500 powered 73 Apollo, 94 Mark VIII
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If all else fails, stick a test light between the cable and battery terminal, if it's on there's a battery drain. Pull fuses until it goes off and check items on that circuit...
 

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Step 1: Have battery charged and tested at a competent shop.

Step 2: Take car to shop and have them check for a "parasitic load".
The method described in the last post used to work back in the 60's but with the advent of computer controls and digital clocks it rarely actually works.
I am not saying it can't work but it might be misleading in a fuel injected car with lots of electronics.
A digital meter should be used to check for a draw to see what is pulling your battery down, and yes, usually you pull fuses until the draw goes away and then start tracing that circuit.
Aftermarket stuff is a big source of parasitic drains. Be careful about plug in accessories, like phone chargers or other electronic equipment.
If it goes dead overnight it should be fairly easy to find.

Good luck.
 

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ewill3rd said:
Step 1: Have battery charged and tested at a competent shop.
Step 2: Take car to shop and have them check for a "parasitic load".
The method described in the last post used to work back in the 60's but with the advent of computer controls and digital clocks it rarely actually works.
I am not saying it can't work but it might be misleading in a fuel injected car with lots of electronics.
A digital meter should be used to check for a draw to see what is pulling your battery down, and yes, usually you pull fuses until the draw goes away and then start tracing that circuit.
Aftermarket stuff is a big source of parasitic drains. Be careful about plug in accessories, like phone chargers or other electronic equipment.
If it goes dead overnight it should be fairly easy to find.
Good luck.
This is true. Basically what he's saying is the test-light procedure will show a pretty big load but you CAN have a load above the standard (what's considered normal) less than or equal to 500mv draw that still wouldn't light a test light. The question at that point would be if it won't light a test light, is the draw large enough to worry about? Unfortunately, that would depend on the draw, how long the car sits, and the condition of the battery.
 

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Anything over 50 mA I consider to be a problem.
The spec on most cars is well below 30 mA.
 

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ewill3rd said:
Anything over 50 mA I consider to be a problem.
The spec on most cars is well below 30 mA.
You just made me realize that I was quoting the wrong figures here. I said mV but I meant mA, sorry. But as I recall, the proper figure was 500mA not 50mA. I could be wrong but I seem to recall half an amp was the cut-off. :hmm:
 
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