Flaky Voltmeter in Dash - Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today



Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 02-14-2009, 02:38 PM   #1
Newb
 
Join Date: Feb 2009
Posts: 8
Ohio Patriot is on a distinguished road
Flaky Voltmeter in Dash

I have a 1997 Wrangler. The battery voltmeter in the dash is flaky. When I start the Jeep it displays 14 V. After about 5 minutes of driving the needle quickly nosedives and points to 9 V. It has done this 3 or 4 times in the past week.

With the needle pointing to 9 V and the engine still running, I measured the voltage at the battery posts using a digital voltmeter - it was 14 V, which meant the alternator was charging the batteries (thank goodness).

So what would make the battery voltmeter in the dash do this? A bad connection somewhere?
Ohio Patriot is offline   Quote
Old 02-14-2009, 02:42 PM   #2
Jeeper
 
afrats's Avatar
 
Join Date: Dec 2008
Location: Colorado Springs, CO
Posts: 1,531
afrats is on a distinguished road
Send a message via MSN to afrats
Or possibly a short in the wiring somewhere.

__________________
My strength is made
perfect in weakness.
2 Corinthians 12:9


afrats is offline   Quote
Old 02-14-2009, 02:44 PM   #3
IITYWTMWYBMAB

::WF Administrator::
 
4Jeepn's Avatar
 
Join Date: Apr 2005
Location: Florence, KY
Posts: 11,347
4Jeepn is on a distinguished road
Bad ground perhaps?
__________________
79.96.85.00.01.97.00.97.93.97.95.94
CJ.XJ.CJ. TJ. TJ.ZJ. TJ.TJ. ZJ.ZJ.YJ. XJ
4Jeepn is offline   Quote
Old 02-24-2009, 02:01 PM   #4
Jeeper
 
AKWrangler's Avatar
 
Join Date: Oct 2008
Location: Alaska
Posts: 83
AKWrangler is on a distinguished road
Quote:
Originally Posted by Ohio Patriot View Post
I have a 1997 Wrangler. The battery voltmeter in the dash is flaky. When I start the Jeep it displays 14 V. After about 5 minutes of driving the needle quickly nosedives and points to 9 V. It has done this 3 or 4 times in the past week.

With the needle pointing to 9 V and the engine still running, I measured the voltage at the battery posts using a digital voltmeter - it was 14 V, which meant the alternator was charging the batteries (thank goodness).

So what would make the battery voltmeter in the dash do this? A bad connection somewhere?
I have been having the same problems except my voltmeter just totally dies. I did replace the battery but I am still having the same problems, I am thinking about replacing the Alternator, did you ever figure out your problem?
AKWrangler is offline   Quote
Old 02-24-2009, 02:23 PM   #5
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 42,046
Jerry Bransford is on a distinguished road
The first thing I do when there's an intermittent electrical problem like that is to remove both of the battery connections, clean the battery posts and inside of the connectors (use a wire brush), then securely reattach them. If you can't get them tight enough, which is common, look at the connector where you'll see two edges that come together that prevent it from getting any tighter. Use a Dremel blade or saw to remove a small amount of material (lead) on both sides so the clamp can be made to close around a smaller diameter so it can once again fit tightely enough around the battery post.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 05-27-2016, 03:40 PM   #6
Jeeper
 
tj_Rubicon's Avatar
 
Join Date: Dec 2014
Posts: 35
tj_Rubicon is on a distinguished road
Did you ever find the problem? Im having a similar issue where the voltmeter, with the key in the on position, shows about 10v. After its running the needle hovers back an forth over 14v.
tj_Rubicon is offline   Quote
Old 05-27-2016, 04:56 PM   #7
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 42,046
Jerry Bransford is on a distinguished road
Quote:
Originally Posted by tj_Rubicon View Post
Did you ever find the problem? Im having a similar issue where the voltmeter, with the key in the on position, shows about 10v. After its running the needle hovers back an forth over 14v.
Did you try the recommendation given in post #5 above?
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 05-27-2016, 06:25 PM   #8
Jeeper
 
Dextreme's Avatar
 
Join Date: Oct 2011
Location: Oregon City, OR
Posts: 6,896
Dextreme is on a distinguished road
Quote:
Originally Posted by tj_Rubicon View Post
Did you ever find the problem? Im having a similar issue where the voltmeter, with the key in the on position, shows about 10v. After its running the needle hovers back an forth over 14v.
Your issue is slightly the opposite of the issue stated by the original poster. Most likely his issue was the Alternator. Yours sounds more like a battery or battery connection issue as Jerry described.
__________________
'99 Chili Pepper TJ - I4 PowerTech motor
33x12.5 DuraTracs
Zone 4.25"
F8.8/Artec Rear
Dextreme is offline   Quote
Old 05-28-2016, 02:14 AM   #9
Jeeper
 
tj_Rubicon's Avatar
 
Join Date: Dec 2014
Posts: 35
tj_Rubicon is on a distinguished road
I cleaned the cables and post like crazy but the problem persists. Ill check again tomorrow and report back.
tj_Rubicon is offline   Quote
Old 05-28-2016, 09:43 AM   #10
Commercial Member

5-Year WF Supporting Member
 
Shark_13's Avatar
 
Join Date: Dec 2012
Location: Idaho
Posts: 3,698
Shark_13 is on a distinguished road
Quote:
Originally Posted by tj_Rubicon View Post
Did you ever find the problem? Im having a similar issue where the voltmeter, with the key in the on position, shows about 10v. After its running the needle hovers back an forth over 14v.
How old is your battery?
__________________
One-of-a-kind wood shift knobs for sale

http://www.wranglerforum.com/f37/han...s-1175625.html
Shark_13 is offline   Quote
Old 05-28-2016, 11:35 AM   #11
Jeeper
 
Dextreme's Avatar
 
Join Date: Oct 2011
Location: Oregon City, OR
Posts: 6,896
Dextreme is on a distinguished road
Quote:
Originally Posted by tj_Rubicon View Post
I cleaned the cables and post like crazy but the problem persists. Ill check again tomorrow and report back.
You may have a dead battery cell, so get your battery checked.
__________________
'99 Chili Pepper TJ - I4 PowerTech motor
33x12.5 DuraTracs
Zone 4.25"
F8.8/Artec Rear
Dextreme is offline   Quote
Old 05-28-2016, 02:58 PM   #12
Jeeper
 
tj_Rubicon's Avatar
 
Join Date: Dec 2014
Posts: 35
tj_Rubicon is on a distinguished road
Brand new battery an alternator.
tj_Rubicon is offline   Quote
Old 05-28-2016, 04:16 PM   #13
Commercial Member

5-Year WF Supporting Member
 
Shark_13's Avatar
 
Join Date: Dec 2012
Location: Idaho
Posts: 3,698
Shark_13 is on a distinguished road
Sometimes the cables can get corroded under the insulation and it's hard to notice...
Have you checked/cleaned the ground locations where it goes to the firewall and frame?
__________________
One-of-a-kind wood shift knobs for sale

http://www.wranglerforum.com/f37/han...s-1175625.html
Shark_13 is offline   Quote
Old 05-28-2016, 04:32 PM   #14
Jeeper
 
Join Date: Apr 2013
Posts: 7,990
Digger84 is on a distinguished road
If you put a voltmeter on battery posts does the voltage engine off reading match the gauge or not?
Digger84 is online now   Quote
Old 05-29-2016, 04:43 PM   #15
Jeeper
 
tj_Rubicon's Avatar
 
Join Date: Dec 2014
Posts: 35
tj_Rubicon is on a distinguished road
I put the meter on the posts before starting and it read 12.65. With the key in the on position the meter read the same but the gauge in the dash read about 10. When its running the gauge shows 14 and the meter on the posts 12.73.
tj_Rubicon is offline   Quote
Old 05-29-2016, 05:19 PM   #16
Jeeper
 
Join Date: Apr 2013
Posts: 7,990
Digger84 is on a distinguished road
So either gauge is off or the PCM is not receiving full battery voltage

The PCM is what really senses voltage then via either the twisted pair CCD bus on 97-2000 or the single wire PCI bus on 2001-2006 the PCM tells the cluster how the gauges should read

I would check voltage at battery pins at PCM

Check battery cables and body ground

And

See what the OBD port says voltage is with key on engine not started
Digger84 is online now   Quote
Old 05-29-2016, 05:21 PM   #17
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 42,046
Jerry Bransford is on a distinguished road
You might have a connection/corrosion/dirt problem between the battery posts and connectors. Physically remove both connectors and wire brush them until they're bright & shiney clean, then reconnect them and make sure both connectors are tight enough so you can't move them around with even considerable hand pressure.

__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
AC & Heater Won't Blow Through Dash Vents BillD TJ Tech Forum 50 08-25-2016 07:49 PM
Sound from under dash? White93ARB YJ General Discussion Forum 10 04-01-2008 03:08 PM
sound bar plug under dash jeep-a-leep YJ Tech Forum 0 10-12-2007 12:30 AM
whats the 'PART TIME' light in my dash telling me? spacomponents TJ Tech Forum 5 10-05-2007 07:16 AM
Dash Lights jeeps&comics YJ Tech Forum 1 06-13-2007 07:47 AM



Download our Mobile App

» Featured Product

All times are GMT -5. The time now is 07:11 AM.


User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC
« Back

Enter your email address:

Delivered by FeedBurner