Crazy engine light

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Doubeleive

Wes
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Yes it has that box on the negative cable . It's a 2006 GMC Yukon XL SLT plus package some places it's called option 2 . But ya voltage meter from 14 to 15.5 volt seems all over the place is right . How does the variable charging work is it built in to the alternator it's 160 amp one ?

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yes it's called regulated voltage control, it's supposed to help maintain the battery and supposedly help with fuel economy which seems to be total b.s. seems more like something they came up with to keep the EPA happy, essentially it makes the alternator digitally controlled they are no longer self excited like the older ones.
 
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Woodblocker55

Woodblocker55

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I'm starting to not believe anything my cluster tells me .. I will double check everything now. How reliable is this digital charging ? It's funny this all started when it said change the oil . So I have same charging system as a 2007-2014 ? In my 2006 ? [emoji849][emoji15]

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2d8ae1dc6916ae7fa9c419c4ab338f20.png
 
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Doubeleive

Wes
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I'm starting to not believe anything my cluster tells me .. I will double check everything now. How reliable is this digital charging ? It's funny this all started when it said change the oil . So I have same charging system as a 2007-2014 ? In my 2006 ? [emoji849][emoji15]

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2d8ae1dc6916ae7fa9c419c4ab338f20.png
yes, I don't know for sure but I think they started using it in 2005, it's still being used on my 2018
 

Rag231

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I was going to reply as well as start my own data collection on this. I get the same reduced engine power situation only when the temps drop into the 40’s and below. The second thing that I noticed is that whatever causes it is time based. I travel the exact same route to my office everyday and there is a green interstate merging sign and I usually get the “ding ding” within 50 to 100 feet of that sign, it’s roughly 2.5 to 3 miles from home. One I stop and shut the vehicle off, I hit the door unlock button on the key fob twice and start it back up. Ride about another 2.5 to 3 miles again and it’s like clock work, “ding, ding”. I can drive 20 more miles to work and will not happen again. Just yesterday I was checking the TPS wiring to make sure it wasn’t anything obvious. I do have the AC Delco replacement harness to install when I get more time. If the temp is in the 60’s or more ,I can ride in the left lane care free, if it’s in the 40’s I better hope that I am in the right lane . I wish there were devices that can be installed while you are driving to give you an exact readout of what’s happening real-time when it happens. I hate this it could be this tied into that , causing this routine. I have several Grand Nationals with Fast XFI and one with the new Holley ECU and I can monitor just about anything that I want. GM should have at least made it to where the vehicle can travel at 35 to 45 mph to get out of harms way or up a hill if necessary. I read a story about a guy that was crossing an intersection when it happened to him and was rear ended. Sorry about the rant just a little frustrated myself. I jiggled the TPS wires and I will check the TAC module as well and progress thru the troubleshooting steps.
 
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Woodblocker55

Woodblocker55

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Yes the voltage meter all over the place like you said about the digital regulator . Both times in picture engine was running . If it's the throttle body modular witch has 181,000 miles on it .. It seems like that's a issue here more outside temp change the more the chance I will get the reduce engine speed code .77f17e9331e31b7720ecd04db198eb6f.jpgcd03583501a29ed73c53aae45c9891da.jpg

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rockola1971

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I was going to reply as well as start my own data collection on this. I get the same reduced engine power situation only when the temps drop into the 40’s and below. The second thing that I noticed is that whatever causes it is time based. I travel the exact same route to my office everyday and there is a green interstate merging sign and I usually get the “ding ding” within 50 to 100 feet of that sign, it’s roughly 2.5 to 3 miles from home. One I stop and shut the vehicle off, I hit the door unlock button on the key fob twice and start it back up. Ride about another 2.5 to 3 miles again and it’s like clock work, “ding, ding”. I can drive 20 more miles to work and will not happen again. Just yesterday I was checking the TPS wiring to make sure it wasn’t anything obvious. I do have the AC Delco replacement harness to install when I get more time. If the temp is in the 60’s or more ,I can ride in the left lane care free, if it’s in the 40’s I better hope that I am in the right lane . I wish there were devices that can be installed while you are driving to give you an exact readout of what’s happening real-time when it happens. I hate this it could be this tied into that , causing this routine. I have several Grand Nationals with Fast XFI and one with the new Holley ECU and I can monitor just about anything that I want. GM should have at least made it to where the vehicle can travel at 35 to 45 mph to get out of harms way or up a hill if necessary. I read a story about a guy that was crossing an intersection when it happened to him and was rear ended. Sorry about the rant just a little frustrated myself. I jiggled the TPS wires and I will check the TAC module as well and progress thru the troubleshooting steps.
Many if not all of the common scanners will show live data stream. You have to have the right data point pulled up though and its hard to look at data...while youre driving. Most of the mid to higher end scanners will actually record your data for playback later. What you need is a ****** clone of the GM Tech 2 scanner. https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20200102183549&SearchText=tech+2 Be sure to specify you want the GM card. Its stupid cheap for under $300 shipped! I use mine all the time. Had it for around 5 years or so now.
 
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Woodblocker55

Woodblocker55

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Ok my alternator checkout all ok had it load tested. And battery was tested all ok.. So that confirms somewhat that it's a grounding issue . I will clean all grounds and add ground from firewall to engine block . I bought 49 inch 6 gauge cable for extra easy excess grounding..If it's a issue we need to make easy to clean . [emoji106] My question is I have the mx plus Bluetooth obd adapter and torq app . I rest my engine light ( money light )with engine off but keey on is that the right way to do it ? I need go back and make sure I'm doing the basics right ..
I did it like this and I have the pending O2 bank one heater.
And that's only code it has now ..

I do have a older autotap for my laptop but I don't think it cover alot of the newer stuff . If anyone knows of updated software for it let me know . I had about $400 tied up in that years ago . It has all the logging real time stuff . Record etc .

After reading I do believe I might have a TPS issue
Because I have had little issues that TPS like not up shifting randomly and random hesitation on acceleration. But like everyone knows it might just be moisture or star alignment deal also.. lol more I read the less I know .. lol [emoji106][emoji41]

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Woodblocker55

Woodblocker55

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Little update . I had to update the firmware on my obd link mx plus adapter bluetooth.. this made all the temp speed and volt match what's on the cluster. Like magic . So all I have left is replace O2 sensor .. bank 1 -1 heater code . Running extra ground cable yet also ..

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BG1988

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yes it's called regulated voltage control, it's supposed to help maintain the battery and supposedly help with fuel economy which seems to be total b.s. seems more like something they came up with to keep the EPA happy, essentially it makes the alternator digitally controlled they are no longer self excited like the older ones.
The float voltage when 'on' should be 13.0-13.1volts if it's showing less then 12.9 you have a connection issue or wire issue somewhere..
 

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