Having problems with your 1998 GMC Sierra ?
Electrical Problem - dead battery
\015 After an alternator failure my 1999 GMC Serria developed a dead battery problem. (replaced battery as well) The radio would stay on with the key off/removed until the battery went dead. I learned that by pulling the 15 amp "radio" fuse under the hood the problem went away. By pulling the fuse I also loose the gas guage, digital odometer, speedometer & tach.\015\012So when we use the truck we put in the fuse ... everything is fine. When we park the truck we pull the fuse and the truck can sit for a week with no problem of starting back up. \015\012\015\012Vin# - 2GTEK19T0X1509572\015\012\015\012Can you help point me in the right direction?\015\012Thank you,\015\012JPL\015
Sounds to me like you may need a new rectifier put in the alternator,a shorted diode in the alternator could be powering up things that should go dead with the key in the off position.To prove this,instead of pulling the fuse,take the plug out of the alternator and if all is well,you have your answer.
Repair Help & Product Troubleshooting for 1998 GMC Sierra
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