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Dual batteries fries radar detector?

  • Thread starter Thread starter mustang_montana
  • Start date Start date Apr 3, 2009

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 3, 2009
#1
  • Apr 3, 2009
  • #1
Still having a problem with this. My dual battery setup is pretty straight forward, two optima yellow tops, one is the main battery connected to the starter and alternator the other is the aux. They are both connected at the positive terminals by a 200a relay that comes on when the ignition is on, and turns off when it is off. There is an overide switch to turn the relay off when I want. Both grounds are to the frame. Don't understand why this setup would fry my radar detector and electronic exhaust valves. I could use some input, all I am thinking now is its a magnetic interference issue as NO fuses are blown and 12v is still getting to everything. Assume I have checked everything simple, and have tested the detector on a completely separate 12v system with the same result (I did and it still did not work). Any suggestions?
 

squeak93

15 Year Member
Jun 2, 2005
2,271
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164
Joplin, Missouri
Apr 3, 2009
#2
  • Apr 3, 2009
  • #2
How many volts are you seeing and is it surging at all?
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 3, 2009
#3
  • Apr 3, 2009
  • #3
Its over 12v with no surge.
 

squeak93

15 Year Member
Jun 2, 2005
2,271
367
164
Joplin, Missouri
Apr 3, 2009
#4
  • Apr 3, 2009
  • #4
Define "over 12v". If its 14.4 or lower its ok. Anything higher I'd say you needs some way to regulate how much is getting into your elec system before you fry your puter.
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 3, 2009
#5
  • Apr 3, 2009
  • #5
usually about battery voltage, 12.6-12.8. i wouldnt think itd be a voltage issue, all the other 12v accesories work as always. what got me thinking it was related to the 200 a battery separator was the fact my exahsut valves don't work anymore, even with the switch working and 12v to everything. they are basically huge electro magnets.
 

1992 2.3LX

New Member
Dec 5, 2002
885
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0
Ky
Apr 4, 2009
#6
  • Apr 4, 2009
  • #6
are you running a battery isolator???
If not it could be part of your problem.
 
R

rpburnette

Member
May 22, 2003
152
0
16
Tampa, FL
Apr 4, 2009
#7
  • Apr 4, 2009
  • #7
I would try something simple and connect your grounds together. Just tie your grounds together with a cable. Even though you have grounded them to the frame which should be the same grounding potential, there might be enough difference to cause problems.
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 4, 2009
#8
  • Apr 4, 2009
  • #8
im running a 200 amp battery separator. i dont have an isolator but i thought it was the same thing essentially, to prevent the batteries from discharging eachother when not in use and the ability to connect/discconect the 2. as for the grounds, i could try that but thats gonna be kind of an awkward mess the way everything is setup right now. thanks guys
 
Z

zigmont

Member
Mar 2, 2009
81
0
6
Apr 4, 2009
#9
  • Apr 4, 2009
  • #9
Dual batteries fries radar detector

Loose/dirty battery terminals can cause all kinds of havoc with electronics. Make sure all connections are clean and tight. Make sure your grounds are connected to clean rust free metal. Dont rely on the bolt to be the conductor when the surface you are grounding to isn't clean (bare) metal. Make sure both the engine and body (frame) are bonded together.
 
S

SONIC02

Member
Feb 9, 2003
70
0
7
Apr 4, 2009
#10
  • Apr 4, 2009
  • #10
Did you try a volt meter just on the ground cable for your radar detector? I would also terminate both grounds at the same point as stated above.
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 7, 2009
#11
  • Apr 7, 2009
  • #11
thanks guys, ill check those things out and put both the terminals together. any other ideas?
 

00stangv6lr

New Member
Sep 25, 2006
61
0
0
Omaha, NE
Apr 7, 2009
#12
  • Apr 7, 2009
  • #12
haha, just a thought but maybe the radar detector just went bad. Have you tried another detector?
 
S

Sanco213

New Member
Oct 8, 2008
23
0
0
Apr 7, 2009
#13
  • Apr 7, 2009
  • #13
did you check what the voltage out of the alternator is? ive sen it where they go bad and charge at a high voltage instead of not at all..
 
R

robt978

New Member
Sep 2, 2008
13
0
0
Apr 8, 2009
#14
  • Apr 8, 2009
  • #14
radar detectors have a fuse built into the plug that plugs into the outlet. Twist-off the little metal ring on the end and you will see the fuse on the end of the cord
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 8, 2009
#15
  • Apr 8, 2009
  • #15
the alternator is new, but i did check the charging voltage and it was about 13.8v on both batteries. i did try another radar detector and it also stopped working after plugging it in, the fuse was fine as well. the first radar detector didnt blow a fuse either, i sent it back to whistler for them to fix. also keep in mind my exhaust valves were also rendered useless after the dual battery setup, with no blown fuses. maybe whistler can tell me what happened to the radar detector. its not the standard model, it is a gauge and remote sensor style one not a windshield one so it could be the gauge part or the antenna module.
 

Mileshigh

New Member
Nov 3, 2008
25
0
0
Raleigh
Apr 8, 2009
#16
  • Apr 8, 2009
  • #16
just a thought trying to remember some of my physics from back in the day but have you used an voltmeter to check the amps at your radar detector? And when you say it quits working like do you mean it lights up and dies or just doesnt ever do anything? how are you plugging it in via power outlet or did you have it wired to the fuse box?
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Apr 8, 2009
#17
  • Apr 8, 2009
  • #17
i cant check the amps on it now, just sent it back to whistler. but it was wired to a fuse block i made with a 3 amp fuse. its possible that the fuse was too many amps and something like 2 amps could have fried the detector, but if thats the case then the second one should have blow a fuse. for this detector there is a gauge display screen and then the sensors and antenna. the only thing that worked was the display screen lighting up. any possible chance the 200 amp battery separator is causing these problems? i still cant see how these heavy duty exhaust solenoids got fried, no blown fuse and still 12v all the way to the solenoid.
 
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