electrical problem

hey if anyone can help i'd appreciate it. just did some wheeling the other day, in my 99 xj sport. on the ride home, my check gauges light came on and my volts had dropped down to the 9 range, just barely above the red line. yet the truck still ran fine. all lights and radio and everything worked perfectley. so i pull over, shut the truck off, and restart it. the volts only rose to 12 when they normally sit at 14. and then after 3-5 minutes of driving the gauge dropped to 9 again. i've tested the battery and the alternator, they both read that they are putting out 14 volts. so i ripped my dash apart to look at the gauge. the plugs that the gauge cluster plugs into on the dash reads around 12 volts and after about 10 minutes it dropped to around 10. so i put it back together and drove it around with a friend following me to see if it would eventually die. and well it drove fine for about 20 minutes. is this just a problem with the gauge or what? i'm stumped.

xjaholic99 said:

hey if anyone can help i'd appreciate it. just did some wheeling the other day, in my 99 xj sport. on the ride home, my check gauges light came on and my volts had dropped down to the 9 range, just barely above the red line. yet the truck still ran fine. all lights and radio and everything worked perfectley. so i pull over, shut the truck off, and restart it. the volts only rose to 12 when they normally sit at 14. and then after 3-5 minutes of driving the gauge dropped to 9 again. i've tested the battery and the alternator, they both read that they are putting out 14 volts. so i ripped my dash apart to look at the gauge. the plugs that the gauge cluster plugs into on the dash reads around 12 volts and after about 10 minutes it dropped to around 10. so i put it back together and drove it around with a friend following me to see if it would eventually die. and well it drove fine for about 20 minutes. is this just a problem with the gauge or what? i'm stumped.

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Sounds like a ground problem.
A 99 will throw a code for low ALT output do you have any codes?

Check the ground from the battery to the engine block and firewall if you have that one. Remove the bolt and clean the connections. Also clean battery terminals. I have seen this several times on xj's and cj's and this usually works.

My 98' did something similiar to this. The serp. belt got a little loose and acted alot like that. Hope this helps.

same problem as parrothead twice on my 99. Once belt was loose after some wet wheeling. Once lost control on a snowy/icy night and knocked the belt off when ended up in a very large wind driven snow bank. I would check belt tightness first, if all ok there check grounds.

hey thanks everyone. i've checked the belt, sorry to include that. it's tight. the bolt from my original battery to firewall broke during the sesion. i noticed it and just moved the ground over to the next bolt. i guess i'll get the rest of the bolt out of there and replace it. thanks for the help guys. i think i just over think the situation, and assume it's the worst thing possible. thanks for bringing me down a noch!!!!!!