 750mV from battery to ground, Tracing the short: any usual suspects? |
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| Prospectfarms |
 Mar 27 2012, 06:32 AM
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Member  Group: Members Posts: 495 Joined: 7-March 11 From: Louisville, KY Member No.: 12,801 Region Association: Upper MidWest  |
Key off. Red terminal to body gives somewhere between 1V and 750mV. (IMG:style_emoticons/default/sad.gif) To me that seems like a bare wire short to ground but I'm not an expert.
Likely spots? Anyplace I could test first before tracing the whole electrical system? How about a short (N.P.I.) list of always-hot wires in the car. Doesn't have to be comprehensive -- just looking for a starting point. Thanks. |
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| Mike Bellis |
Mar 27 2012, 10:00 PM
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Resident Electrician Group: Members Posts: 8,347 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None 
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The voltage you are reading could be capacitance from the ECU, coil or radio. Really the way you are testing will tell you nothing. You need to do a current test is you are worried about drain. 750mV is nothing and as long as you have electrical loads in the car, your test will tell you no valuable information. Remove the switch to test it properly. If you had a real direct short, your voltage reading would be 12V and not 1V.
I think you are worried for nothing. 20+ years of electrical troubleshooting experience. |
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Posts in this topic
Prospectfarms 750mV from battery to ground Mar 27 2012, 06:32 AM
stugray What?
Does the car run?
You should have ~12-13 Vo... Mar 27 2012, 08:25 AM
Prospectfarms
What?
Does the car run?
You should have ~12-13 V... Mar 27 2012, 08:49 PM ape914
What?
Does the car run?
You should have ~12-13 ... Mar 27 2012, 09:28 PM Valy
What?
Does the car run?
You should have ~12-13 ... Mar 27 2012, 09:36 PM Prospectfarms
[quote name='Prospectfarms' post='1655151' date='... Mar 27 2012, 09:51 PM Valy 1St, your battery is dead.
Disconnect it and measu... Mar 27 2012, 10:36 AM Prospectfarms
1St, your battery is dead.
Disconnect it and meas... Mar 27 2012, 08:53 PM underthetire To check ghost drains
Remove red wire from batter... Mar 27 2012, 11:36 AM Prospectfarms
To check ghost drains
Remove red wire from batte... Mar 27 2012, 08:57 PM Spoke Here's some basic voltages to check.
1) Measu... Mar 27 2012, 01:01 PM Prospectfarms
Here's some basic voltages to check.
1) Meas... Mar 27 2012, 08:59 PM Prospectfarms If I understand what your saying, if there was onl... Mar 27 2012, 09:40 PM Prospectfarms
The voltage you are reading could be capacitance ... Mar 27 2012, 10:32 PM rhodyguy try taking the inline fuse for the stereo out and ... Mar 28 2012, 11:18 AM kg6dxn You want to measure amperage. You want to see less... Mar 28 2012, 05:18 PM Prospectfarms Dugout my real mulitmeter. Replaced fuse and batte... Mar 28 2012, 07:26 PM Valy You are good although 25mA for the stereo is a bit... Mar 28 2012, 08:32 PM Prospectfarms
You are good although 25mA for the stereo is a bi... Mar 29 2012, 05:48 AM Valy What else is always on? Clock? Mar 29 2012, 08:43 AM warrenoliver
What else is always on? Clock?
when I had batt... Mar 29 2012, 11:20 AM Prospectfarms Sorry for the delay responding. Unfortunately I do... Mar 29 2012, 10:36 PM kg6dxn Your drain seems a little high with no radio or cl... Mar 29 2012, 10:47 PM Prospectfarms
Your drain seems a little high with no radio or c... Mar 30 2012, 09:34 PM |
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