[SolidGoldCaddy]

Hey guys, hoping this happened to someone else and it's and easy fix/cheap.

So I just started my truck, let it warm up for 10-15 before driving, and then when I got to my destination, put it in park and sat for a minute. The radio/navigation won't turn on. It doesn't display anything. When I hit the power button, the backlight comes on and the time, but it won't power on. Also the drivers and passengers side doors button illumination is being weird. One minute it's fine, the next they flicker off, then back on. The voltmeter is reading higher than what I think is normal, and it's jogging between 15-16 volts. Then just as I was about to leave, the meter dropped down below 14 volts and the idle roughened up a bit. No engine or battery lights, no warning lights of any kind. 86K miles. Runs and operates fine.

Really hoping to shed some light on this issue and find a solution.

Thanks a ton in advance fellas!

 

[the cadillac man]

Hey guys, hoping this happened to someone else and it's and easy fix/cheap.

So I just started my truck, let it warm up for 10-15 before driving, and then when I got to my destination, put it in park and sat for a minute. The radio/navigation won't turn on. It doesn't display anything. When I hit the power button, the backlight comes on and the time, but it won't power on. Also the drivers and passengers side doors button illumination is being weird. One minute it's fine, the next they flicker off, then back on. The voltmeter is reading higher than what I think is normal, and it's jogging between 15-16 volts. Then just as I was about to leave, the meter dropped down below 14 volts and the idle roughened up a bit. No engine or battery lights, no warning lights of any kind. 86K miles. Runs and operates fine.

Really hoping to shed some light on this issue and find a solution.

Thanks a ton in advance fellas!

I had something like this happen to me and it happened to be the battery cables was loose and given how you said the voltage gauge is doing it may be both the battery and alternator needs checking and testing at a parts place

 

[wake]

High voltage sounds to me like the voltage regulator, but the rough idle when it drops to 14 volts doesn't make sense to me the vehicle should run just fine. As the above poster suggested, check the battery cable connections at the battery and the other end attachment points for problems.

From what I remember on Escalade, Tahoe, and Yukons the voltage regulator is external to the alternator. I believe it's the black box on the negative cable coming off the battery.

These vehicles should also give some indication in the DIC like, 'service charging system', 'battery not charging', 'charging system failure'. Those I listed come from the 2005 owner's manual. I received the, 'service charging system' message when my alternator started going out intermittently a couple of days before I replaced it.

Good luck, electrical gremlins are the problems I hate the most.

 

[the cadillac man]

High voltage sounds to me like the voltage regulator, but the rough idle when it drops to 14 volts doesn't make sense to me the vehicle should run just fine. As the above poster suggested, check the battery cable connections at the battery and the other end attachment points for problems.

From what I remember on Escalade, Tahoe, and Yukons the voltage regulator is external to the alternator. I believe it's the black box on the negative cable coming off the battery.

These vehicles should also give some indication in the DIC like, 'service charging system', 'battery not charging', 'charging system failure'. Those I listed come from the 2005 owner's manual. I received the, 'service charging system' message when my alternator started going out intermittently a couple of days before I replaced it.

Good luck, electrical gremlins are the problems I hate the most.

Wake the voltage regulator is in the PCM which sends a signal to the alternator to charge the battery

 

[wake]

Wake the voltage regulator is in the PCM which sends a signal to the alternator to charge the battery

My shop manual lists that black box I referred to as the, 'Generator Battery Control Module', it works with the PCM to act as a voltage regulator. It's more complicated than I thought though. It's on the class II data bus and controls the generator field control circuit according to the shop manual. The complete description is in Vol 2, pg 6-779 if you have the manual.

 

[6lbsofSound]

2005 and up have a BCM battery control module. The PCM is not the cause. If that battery and alternator check out as good it is the BCM by the battery or the alternator wire might have some corrosion on it. Wake is correct. The BCM can go into an economy mode and regulate from their sending the readings all over the place on a multi meter or dash. It generally won't throw a code when the battery and alternator are good.

 

[SolidGoldCaddy]

Wow guys. Overwhelming and thorough responses. I will clean and check the connections and try that first. Then have the alternator and battery tested if it persists. Any idea where to get a BCM should that be the case? Is it plug and play or will it require a Tech tool at a dealer to program and sync to my truck?

Thanks so much for the help fellas. It's much appreciated I this end.

 

[6lbsofSound]

The BCM or voltage reg is right next to the battery small black box. Dealer item usually, unless you can find it online.

 

[the cadillac man]

The BCM or voltage reg is right next to the battery small black box. Dealer item usually, unless you can find it online.

Gm parts direct is a online site although I don't know if they would have this particular part
www.gmpartsdirect.com
Then put in the year make and model along with the trim and engine size and check under electrical

 

[Cadillac Customer Service]

Wow guys. Overwhelming and thorough responses. I will clean and check the connections and try that first. Then have the alternator and battery tested if it persists. Any idea where to get a BCM should that be the case? Is it plug and play or will it require a Tech tool at a dealer to program and sync to my truck?

Thanks so much for the help fellas. It's much appreciated I this end.

Glad to see the community stepped in to assist, SolidGoldCaddy! I hope you'll keep us posted on your progress. Like The Cadillac Man, I also recommend looking into gmpartsdirect.com for helpful information. (GM neither endorses nor maintains this site, however, and will not be responsible for its contents.)

Katie
Cadillac Customer Service

 

[SolidGoldCaddy]

Hey guys just wanted to follow up with you and let you know, I changed out the battery for an AC Delco right from the dealership and got rid of the Walmart battery that was in there. The battery was 15 days out of the three-year warranty. No problems since battery swap. Thanks for all the help that everyone contributed, I really appreciate it.

 

[Kgraves691]

Hello I'm having a little problem with my 05 escalade esv 6l. No power no start nothing this morning. Go back out 10 minutes later and starts fine... did notice voltage gauge on dash been jumping from 13-17 some time... runs drives fine no dic mess, no warning lights...

 

[Cameron0588]

Hello I'm having a little problem with my 05 escalade esv 6l. No power no start nothing this morning. Go back out 10 minutes later and starts fine... did notice voltage gauge on dash been jumping from 13-17 some time... runs drives fine no dic mess, no warning lights...

Please keep us posted if it does it again.