High voltage, but not really.
Thread Starter
|
Registered User
Joined: Oct 2016
Posts: 20
Likes: 0
From: Gibsons, BC, Canada
High voltage, but not really.
2001 2500 4x4, 5.9, auto trans.
Got "check gauges" warning chime and indicator. Battery voltage pinned at ~ 18V, according to the instrument panel gauge.
I pulled over, shut the engine down and re-started. Everything good until I get home.
This sequence of events repeated itself for several days.
"OK" I sez to myself, " Should be nothing wrong with the alternator, must be the regulator circuit in the PCM". So, installed an external regulator. Same problem.
"So" I sez to myself, " I wonder if the instrument panel voltmeter is telling me the truth"?
I checked the voltage at the battery with the instrument panel gauge indicating ~ 18V. 14.8 V on my trusty Fluke 87.
No problem with the alternator or the new external regulator.
Ever since, when I take the truck out, it will give me the warning and high voltage on the gauge. I ignore it, and after several minutes, the voltage gets back to normal and the warning goes away. Sometimes it will stay this way until I get home, sometimes it will cycle several times until I get home.
What gives? Anyone ever have a similar problem?
Got "check gauges" warning chime and indicator. Battery voltage pinned at ~ 18V, according to the instrument panel gauge.
I pulled over, shut the engine down and re-started. Everything good until I get home.
This sequence of events repeated itself for several days.
"OK" I sez to myself, " Should be nothing wrong with the alternator, must be the regulator circuit in the PCM". So, installed an external regulator. Same problem.
"So" I sez to myself, " I wonder if the instrument panel voltmeter is telling me the truth"?
I checked the voltage at the battery with the instrument panel gauge indicating ~ 18V. 14.8 V on my trusty Fluke 87.
No problem with the alternator or the new external regulator.
Ever since, when I take the truck out, it will give me the warning and high voltage on the gauge. I ignore it, and after several minutes, the voltage gets back to normal and the warning goes away. Sometimes it will stay this way until I get home, sometimes it will cycle several times until I get home.
What gives? Anyone ever have a similar problem?
Grand Champion
Joined: Apr 2008
Posts: 7,055
Likes: 7
From: Lee County, North Carolina
The same thing happened to me a couple times, years ago.
Once it was a loose connection on the battery because one of the two parts of the stock bands got eaten up by battery acid. A penny used as a spacer to get a tight connection fixed it on the side of the road until I got a lead terminals for it.
It happened again a while later and a scraping of the terminals and the battery posts with a flat head screwdriver on the side of the road fixed it.
I now have an AGM battery that doesn't breathe like lead acid batteries do and I haven't had a corrosion issue since.
Once it was a loose connection on the battery because one of the two parts of the stock bands got eaten up by battery acid. A penny used as a spacer to get a tight connection fixed it on the side of the road until I got a lead terminals for it.
It happened again a while later and a scraping of the terminals and the battery posts with a flat head screwdriver on the side of the road fixed it.
I now have an AGM battery that doesn't breathe like lead acid batteries do and I haven't had a corrosion issue since.
Thread Starter
|
Registered User
Joined: Oct 2016
Posts: 20
Likes: 0
From: Gibsons, BC, Canada
Interesting!
I suspected that at the beginning so one of the first things I did was to take my battery connections off, clean them and re tighten, even through they looked good. I also checked resistance from the battery post to the engine ground point and the chassis ground point near the PCM. I also checked it at the alternator. All was good.
I don't know if the voltage sensing circuit has a dedicated positive and negative wires or not, I rather doubt it.
I suspected that at the beginning so one of the first things I did was to take my battery connections off, clean them and re tighten, even through they looked good. I also checked resistance from the battery post to the engine ground point and the chassis ground point near the PCM. I also checked it at the alternator. All was good.
I don't know if the voltage sensing circuit has a dedicated positive and negative wires or not, I rather doubt it.
Registered User
Joined: Jul 2017
Posts: 3
Likes: 0
Even added a secondary full time Digital Battery Monitor (reading only battery)
no change at battery when OEM voltmeter read 18+.
Not even .01 volt difference at batt.
I exchanged the ECM,
(Electronic Control Module), with one from the recycler,
and all was well for the next 2 years.
Now I have a no charging issue...
have ordered another ECU.
Chache'