Crazy engine light

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
26,532
Reaction score
39,948
Location
Stockton, Ca.
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 ?

Sent from my LGL84VL using Tapatalk
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.
 
OP
OP
Woodblocker55

Woodblocker55

Full Access Member
Joined
Apr 13, 2019
Posts
667
Reaction score
420
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]

Sent from my LGL84VL using Tapatalk
2d8ae1dc6916ae7fa9c419c4ab338f20.png
 
Last edited:

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
26,532
Reaction score
39,948
Location
Stockton, Ca.
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]

Sent from my LGL84VL using Tapatalk
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

TYF Newbie
Joined
Mar 12, 2015
Posts
7
Reaction score
5
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.
 
OP
OP
Woodblocker55

Woodblocker55

Full Access Member
Joined
Apr 13, 2019
Posts
667
Reaction score
420
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

Sent from my LGL84VL using Tapatalk
 

rockola1971

Full Access Member
Joined
Dec 29, 2016
Posts
2,643
Reaction score
3,599
Location
Indiana (formerly IL)
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.
 
Last edited:
OP
OP
Woodblocker55

Woodblocker55

Full Access Member
Joined
Apr 13, 2019
Posts
667
Reaction score
420
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]

Sent from my LGL84VL using Tapatalk
 
OP
OP
Woodblocker55

Woodblocker55

Full Access Member
Joined
Apr 13, 2019
Posts
667
Reaction score
420
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 ..

Sent from my LGL84VL using Tapatalk
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,969
Reaction score
1,352
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..
 

Forum statistics

Threads
132,788
Posts
1,874,274
Members
97,630
Latest member
Acha
Top