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Check Gauge Light, Battery voltage spike, erratic speedo readings

Old Apr 22, 2018 | 09:11 PM
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Default Check Gauge Light, Battery voltage spike, erratic speedo readings

My 01 Ram 1500 instrument panel has been acting up. At first my check gauge light came on and my battery voltage spiked. after i stopped the truck the light went off and went to normal. on the highway the same thing happened but this time my speedo started to bounce around i was doing 70 and it went down to 50 then started to bounce down to 0. Are these problems related? I installed a new battery yesterday and a new alternator 3 weeks ago.

Thanks!

Mark
 
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Old Apr 22, 2018 | 09:15 PM
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What I also forgot to mention was that I have a P1757 code. Im thinking the speedo behavior has something to do with my speed sensor/governor sensor, hence the code.
 
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Old Apr 22, 2018 | 09:35 PM
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What prompted the battery and alternator replacement?
 
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Old Apr 22, 2018 | 09:39 PM
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I replaced the alternator because the battery meter dropped to 8 volts and it was making an awful bearing noise. it also smelled like the alternator was burning. I had just replaced it a year before. I tested my battery and it wasn't putting out the cca that it was rated for, also it kept building up corrosion.
 
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Old Apr 23, 2018 | 08:16 AM
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Batteries will build up that white crap no matter what you do.

Pull the alternator, and have it load tested. If it tests good, likely your voltage regulator is having some issues. Unfortunately, the voltage regulator is part of the PCM......
 
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Old Apr 23, 2018 | 09:46 AM
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I would like to replace my PCM. Can I just plug an play a refurbished one of do I have to get it programmed?
 
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Old Apr 23, 2018 | 10:39 AM
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Could it be the gauge cluster acting up? My speedo is acting funny too. But that could be related to my transmission speed sensor. Not sure
 
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Old Apr 23, 2018 | 03:53 PM
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98 and newer trucks need the VIN flashed to the PCM, otherwise, it gets annoyed.
 
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Old Apr 23, 2018 | 05:01 PM
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Sad day, did some tests with the volt meter. The highest voltage reading was 16.02. When I turned on a lot of electronics, the volt readings went down. It’s the pcm..... I probably get an external regulator and bypass the one in the computer.
 
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Old Apr 23, 2018 | 05:36 PM
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Remanufactured PCM ordered, It’s a week out. One thing I am concerned about is what made the regulator fail n the first place and will it happen to my new one.
 
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