Random Battery Death?
Postmaster
Joined: Mar 2013
Posts: 3,066
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From: Over There
Additionally if you want to be really trick and 100% sure in the future get a battery disconnect solenoid and the buzzer. Wire it so with the solenoid off power can only flow through the buzzer(connected to both posts of solenoid). So then when you turn the rig and thus the solenoid off if the buzzer sounds you have a draw.
I haven't tried the buzzer thing, just thought if it, I might add one though. I do have one of these in my rig though.
I haven't tried the buzzer thing, just thought if it, I might add one though. I do have one of these in my rig though.
Postmaster
Joined: Mar 2013
Posts: 3,066
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From: Over There
I haven't used the HF tester, but I personally don't like anything except a good DMM if series load testing sensitive electronics. The only reason is that the resistive value of a DMM is very low, which keeps the voltage at the upstream devices closer to battery voltage. Series resistors are voltage dividers. Anything placed in series of the tested circuit will have an affect on the voltage available to the other loads in the circuit. Test lights, and buzzers aren't huge resistors, but more than I'm comfortable with when placed in series with a PCM, or expensive radio head unit. My $.02, YMMV, TIFWIW.
I'm not saying you have to go get a Fluke, I got an inexpensive one that looks a lot like the cheap HF one that I've had for many years and has been very dependable.
Lead Driver
Joined: Nov 2007
Posts: 5,139
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You're too concerned about an issue that isn't an issue at all. You ever watch battery/system voltage during cranking/starting, Even the best system will go from 12.6 to 10 to 14 in a few seconds? Or notice, lights dim, radio stops, etc. PCMs, pricey radios, etc. are designed for large voltage variations, a buzzer in series will have no concernable effect.
A test light in series with the entire load of the vehicle will be negligible, but when testing small, individual component loads, the numbers change drastically.
Postmaster
Joined: Mar 2013
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From: Over There
As for the first part, give me a min I'll do the math, it's just Ohms law.
Postmaster
Joined: Mar 2013
Posts: 3,066
Likes: 7
From: Over There
A 10W bulb has 15.876Ohms resistance.
That's a 4.76V drop, 12.5-4.76 = 7.74V
Lead Driver
Joined: Nov 2007
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Lead Driver
Joined: Nov 2007
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I don't understand what you mean by the computer reset/dome light relation. You can pull then dome light fuse early on to keep the lights off while you proceed. Are you testing by yourself now?
Thread Starter
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New User
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Ya its just me doing the testing
Lead Driver
Joined: Nov 2007
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To save time you can pull the fuses in organized groups, say 5 at a time, then go to the front and check. Take out the fuses for the constant loads in the first group. Then its a matter of finding the individual circuit(s) that are causing the problem. There's another load test to the alternator, but it gets saved for last, as it can be dangerous if you're not very careful.
Lead Driver
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We've driven Seattle to San Jose, and L.A. to Baja. The only stretch of west coast shoreline we haven't hit is in your backyard. I will fill that gap, and don't be surprised if I end up at your door. I know where you live. Remember when I sent the CBetrs back in the day?
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From: Central Coast of CA
Back-up cam. 
I've always obtained my CBetr mirrors from their website.
And yes, before you ask, I have installed the back-up cam for my wife on her Ex. No, I am not lying....honest....seriously, I'm telling the truth....the whole truth and nothing but....really....believe me....
Stewart
I've always obtained my CBetr mirrors from their website.
And yes, before you ask, I have installed the back-up cam for my wife on her Ex. No, I am not lying....honest....seriously, I'm telling the truth....the whole truth and nothing but....really....believe me....
Stewart