[rhinocerossoftdrink]

Good point. Under trunk storage is where mine will go along with tire inflator and battery jumper

 

[hightech-guy]

Good point. Under trunk storage is where mine will go along with tire inflator and battery jumper

Yeah, I figured center console is perhaps best because of possible inability to open the glovebox electronically. And that odds are I'll have something in the trunk when I need to do the reset, so didn't want the wrench buried under cargo.

 

[davedogcaddy]

Yeah - I'm in the same boat - if I'm in town I have a couple large tool bags and other IT related items in the cargo area, if I'm out of town I have luggage. Center console it is...lol

 

[hightech-guy]

Yeah - I'm in the same boat - if I'm in town I have a couple large tool bags and other IT related items in the cargo area, if I'm out of town I have luggage. Center console it is...lol

A perfect place would be in the frunk. Oh wait...

 

[Jimpilot]

I have a small tool kit I think I’ll put it in, store in the the rear well is what I’m planning

 

[Tripwire]

I'm loitering on this thread....no vested interest.....you should not have to take such measures right? a 65K+ car ........

 

[davedogcaddy]

I'm loitering on this thread....no vested interest.....you should not have to take such measures right? a 65K+ car ........

I mean you are not wrong - but this isn't really a 'new' thing either. Once computers got heavily involved... I'm in IT - so I'm not surprised.

For me my first car that would occasionally have software type glitches and require a 'reboot' was a 2005 model. Every car I've had since then has had some occasional software glitches that reboots fixed. Mostly soft reboots (power down the car for 20 mins).

I have put 5000 miles on my Lyriq and not seen the dealer yet. This is my 2nd hard reboot.

Depends on your expectations. Mine have been exceeded so far.

Over time I'm confident as more updates roll out things will smooth out even more.

 

[medic7235]

If this is an occasional procedure, and sometimes necessary at inconvenient times or places, would something like this Battery Disconnect be beneficial?

 

[hightech-guy]

If this is an occasional procedure, and sometimes necessary at inconvenient times or places, would something like this Battery Disconnect be beneficial?

It's hopefully not needed as much as it was even 6 months ago. The people in China did something like this - the early Lyriq's were very buggy there and in need of frequent hard resets. I'm not sure if that switch will fit though - not much room under the bracket.

 

[Jimpilot]

I know this thread is dated and the number of 12 volt incidents are nearing zero, but a few questions “just in case” . If I find myself with a dead 12v battery and I charge it up overnight and it holds a charge is it ok to drive car to dealer or more? as part of the battery charge you disconnect battery, so it seems like you’ve done a hard reset, it is possible it will unstick, stuck module?

Just trying to figure out how to handle it if it happens, after car sitting so long I’m not sure what shape the 12v battery will be in.

 

[hightech-guy]

I know this thread is dated and the number of 12 volt incidents are nearing zero, but a few questions “just in case” . If I find myself with a dead 12v battery and I charge it up overnight and it holds a charge is it ok to drive car to dealer or more? as part of the battery charge you disconnect battery, so it seems like you’ve done a hard reset, it is possible it will unstick, stuck module?

Just trying to figure out how to handle it if it happens, after car sitting so long I’m not sure what shape the 12v battery will be in.

Once the car is on and working, the 12V system is powered by the high voltage battery via the DC-DC converter. So you can get it to the dealer, instead of having it towed.

Understand this thread isn't really regarding the 12V drain issue - just how to disconnect and reset the car if it got into an unhappy state. Those instances are also much rarer now versus earlier in the year.

 

[Jimpilot]

Once the car is on and working, the 12V system is powered by the high voltage battery via the DC-DC converter. So you can get it to the dealer, instead of having it towed.

Understand this thread isn't really regarding the 12V drain issue - just how to disconnect and reset the car if it got into an unhappy state. Those instances are also much rarer now versus earlier in the year.

I guess I’m confused, this isn’t the same procedure you would use to disconnect the 12v battery to recharge it? Or do you need to disconnect it to recharge it ?

 

[hightech-guy]

I guess I’m confused, this isn’t the same procedure you would use to disconnect the 12v battery to recharge it? Or do you need to disconnect it to recharge it ?

Yes, you need to disconnect 12V battery to recharge it - given the parasitic draw issues that have plagued the car (and cause the 12V battery to deplete). There is a whole thread on this, with more detail on how to hookup the charger. This thread was just about disconnecting and reconnecting the battery - not recharging anything.

Probably this post has the most info regarding recharging a Lyriq with a dead 12V battery...

12v battery issue ?

2023 RWD Model. Not what I wanted my first post to be about, but today I couldn't open the doors to my Lyriq or anything else. I had a family emergency last night and didnt get home until very late. My car was at 40%, went to bed and realized I forgot to plug it in. I decided to wait until...

www.cadillacforums.com

 

[Jimpilot]

Yes, you need to disconnect 12V battery to recharge it - given the parasitic draw issues that have plagued the car (and cause the 12V battery to deplete). There is a whole thread on this, with more detail on how to hookup the charger. This thread was just about disconnecting and reconnecting the battery - not recharging anything.

Probably this post has the most info regarding recharging a Lyriq with a dead 12V battery...

12v battery issue ?

2023 RWD Model. Not what I wanted my first post to be about, but today I couldn't open the doors to my Lyriq or anything else. I had a family emergency last night and didnt get home until very late. My car was at 40%, went to bed and realized I forgot to plug it in. I decided to wait until...

www.cadillacforums.com

That’s what I needed thanks

 

[Luxiondrive]

Hey, new guy here, so I'll tread lightly. Clearly a lot of forum users have been able to recover from glitches using this forum procedure. But, it is a bit different than the GM LYRIQ reset procedure, which might actually be a bit easier, so I'm wondering if you have considered the GM procedure and why that is not being used?

There are two main differences. First, they wait for the DC/DC converter to turn off, then open the green HV disconnect switch on the passenger side front under the passenger side front plastic cover. As you know, lifting the 12V ground forces the HV contactor open. GM seems to have some wear issues with the contactor and wants to open it only under the no-load condition to maximize contactor life. So, according to GM, it is not optional to wait for the DC/DC converter to turn off. Also, opening the green hv safety switch is not just for further HV work, but a generally conservative way to ensure the hv contactor for the converter does not operate.

Unless the 12V battery is being replaced, GM guidence is to not lift the 12V battery terminal. Rather, the GM procedure is to lift the 12V ground cable from terminal on the 12V sensor, a 10mm nut. It really is just as easy, if not easier than lifting the terminal and battery computer. The reasoning is that lifting the 12V sensor causes the need for a battery sensor computer reset. You know that most of them can reset over many hours and drive cycles by themselves, or there is a reset procedure. Before reset, a recently disconnected battery computer sensor sends 12V 65% soc and no longer updates until the reset is complete. By lifting only the ground cable, you get the same 12V hard reset without disturbing the operation of the 12V battery sensor computer on the negative terminal of the 12V battery.

Probably no one is going to be electrocuted or die, but is not quite the LOL either. The GM procedure is best practice both for safety, less wear and tear on the HV contactor, and no need to reset the 12V battery sensor computer which continues to function normally with good uninterrupted data.

Here is a post I have been working on. Honestly, I did not want to offend as a new member, but I think this alternative GM procedure might be considered:

GM LYRIQ 12V battery ground disconnect procedure

Fortunately, 12V resets are less common now as I read on the forums. As a new LYRIQ owner and EV gearhead, I have been reading GM docs on the 12V system and resets. The recommended procedure is a bit different some of those posted. The gist of it is, do not remove the 12V negative terminal unless you need to, such as replacing the 12V battery.

Short summarized version of GM procedure:

• Remove the center trunk plastic cover (6 plastic clips).
• Remove both side covers (more of the same plastic clips).
• Use a voltmeter to wait for the battery charger to turn off, generally below 12.9V. Do not remove the 12V ground yet.
• On the passenger side front side wall open the green HV cutoff switch. Do not open the HV cutoff switch until the battery charger is off (step 3)
• Remove the top metal battery clamp (2x 10mm nuts)
• Remove the outboard ground lug bolted (10mm) to the battery monitor (the cable that goes to chassis ground). Do not remove the 12V battery terminal
• After the hard reset by removing the 12V ground cable, reverse the process above.

Note, the green hv safety switch is not actually open until the word "ON" in green is no longer showing and "OFF" appears, I still need to make a picture of the hv safety switch fully open.

GM says do this only when directed; however many EV owners have had to do a hard reset on occasion to try to clear a problem.

They don’t want to remove 12V and open the HV contactor under load. That is why they want to be sure the 12V charger is off. Also, they want to retain the current operation of the 12V battery monitor so that it does not need to be reset over many hours or several drive cycles.

The formal procedure locks out the green HV switch with a lock, but here there is no further maintenance over hours or where other people might work on vehicles, so that is probably overkill if just doing a hard reset. But, opening the HV switch is not just for HV work, it is standard practice now for many EVs including LYRIQ to guarantee the HV contactors don’t close.

 

[hightech-guy]

Hey, new guy here, so I'll tread lightly. Clearly a lot of forum users have been able to recover from glitches using this forum procedure. But, it is a bit different than the GM LYRIQ reset procedure, which might actually be a bit easier, so I'm wondering if you have considered the GM procedure and why that is not being used?

There are two main differences. First, they wait for the DC/DC converter to turn off, then open the green HV disconnect switch on the passenger side front under the passenger side front plastic cover. As you know, lifting the 12V ground forces the HV contactor open. GM seems to have some wear issues with the contactor and wants to open it only under the no-load condition to maximize contactor life. So, according to GM, it is not optional to wait for the DC/DC converter to turn off. Also, opening the green hv safety switch is not just for further HV work, but a generally conservative way to ensure the hv contactor for the converter does not operate.

Unless the 12V battery is being replaced, GM guidence is to not lift the 12V battery terminal. Rather, the GM procedure is to lift the 12V ground cable from terminal on the 12V sensor, a 10mm nut. It really is just as easy, if not easier than lifting the terminal and battery computer. The reasoning is that lifting the 12V sensor causes the need for a battery sensor computer reset. You know that most of them can reset over many hours and drive cycles by themselves, or there is a reset procedure. Before reset, a recently disconnected battery computer sensor sends 12V 65% soc and no longer updates until the reset is complete. By lifting only the ground cable, you get the same 12V hard reset without disturbing the operation of the 12V battery sensor computer on the negative terminal of the 12V battery.

Probably no one is going to be electrocuted or die, but is not quite the LOL either. The GM procedure is best practice both for safety, less wear and tear on the HV contactor, and no need to reset the 12V battery sensor computer which continues to function normally with good uninterrupted data. View attachment 653069 View attachment 653070

Here is a post I have been working on. Honestly, I did not want to offend as a new member, but I think this alternative GM procedure might be considered:

GM LYRIQ 12V battery ground disconnect procedure

Fortunately, 12V resets are less common now as I read on the forums. As a new LYRIQ owner and EV gearhead, I have been reading GM docs on the 12V system and resets. The recommended procedure is a bit different some of those posted. The gist of it is, do not remove the 12V negative terminal unless you need to, such as replacing the 12V battery.

Short summarized version of GM procedure:

• Remove the center trunk plastic cover (6 plastic clips).
• Remove both side covers (more of the same plastic clips).
• Use a voltmeter to wait for the battery charger to turn off, generally below 12.9V. Do not remove the 12V ground yet.
• On the passenger side front side wall open the green HV cutoff switch. Do not open the HV cutoff switch until the battery charger is off (step 3)
• Remove the top metal battery clamp (2x 10mm nuts)
• Remove the outboard ground lug bolted (10mm) to the battery monitor (the cable that goes to chassis ground). Do not remove the 12V battery terminal
• After the hard reset by removing the 12V ground cable, reverse the process above.

GM says do this only when directed; however many EV owners have had to do a hard reset on occasion to try to clear a problem.

They don’t want to remove 12V and open the HV contactor under load. That is why they want to be sure the 12V charger is off. Also, they want to retain the current operation of the 12V battery monitor so that it does not need to be reset over many hours or several drive cycles.

The formal procedure locks out the green HV switch with a lock, but here there is no further maintenance over hours or where other people might work on vehicles, so that is probably overkill if just doing a hard reset. But, opening the HV switch is not just for HV work, it is standard practice now for many EVs including LYRIQ to guarantee the HV contactors don’t close.

All good info you have - thanks for sharing that. Regarding your questions, I'll comment from my end from personal experience.

• The suggestions here were in absence of any GM procedure at the time - just something an end user could easily do in either an emergency or last resort - and with basic tools. Use of a multi-meter to confirm the DC-DC converter is off is listed as a tip however - if don't want to empirically deduce the car is off by checking for functionality.
• There also some extra things mentioned here in an attempt to not stump / annoy people. Things that might be assumed by a GM tech, but not a shade tree. Such as the car locking, the alarm going off, temporary errors after doing this, etc. Tried to add some detail on how to avoid that, or what to do if things happen.
• It is actually a bit of a pain to remove the left and right plastic shields, to gain access to all the things mentioned in the GM procedure. They slide into the clips on the fender side, and it is a bit tricky. But not hard to just pop off the center shield.
• Disconnecting the negative wire from the car instead of removing at the terminal is good approach, but you can't use the 10mm quick tool that a lot of folks suggested. And the battery is still connected to the sensor, and some desire to want everything on the car not receiving power.
• So the GM procedure of also removing the high voltage interlock is kinda a belt and suspenders approach. If the DC-DC converter is off (timed out, or battery removed), it isn't coming back on. I suppose the thought is you could have verified the car was asleep, but it decides to wake up right before you remove the negative cable. Due to a bit more difficult access of those side panels, and the possibility of disabling the car completely if something goes wrong, just a lot to do for that edge case. Clearly not a bad thing and certainly fine if you are in the comfort of home in a garage, but not something I'd be doing if stuck on the side of the road, etc.
• So disconnection of the 12V battery was a thing with early Lyriqs to solve system gremlins, but this hasn't found to be really needed anymore (that is, until GM hoses us again with another parasitic drain issue). But letting the car sleep seems to solve any system issues at the present time. And any infotainment issues are solved with the 10 second phone hang up reboot procedure. So the 12V disconnect procedure now is more useful in the scenario of the parasitic drain, where the 12V battery has died. And in that case, the DC-DC converter is already off of course. Really just need the battery disconnected from the car so it can be directly charged, with the load from the vehicle removed. Or if the battery isn't totally dead and bounces back up a bit to have enough juice to kick the contractor and DC-DC converter on when the negative is reconnected, a big bonus not needing an external charger.

So that would be my logic, good or bad. Definitely what you share from the GM procedure is very good info also - many thanks.

 

[Boatbuilder68]

Could you amplify on your comment regarding the infotainment reset? “…any infotainment issues are solved with the 10 second phone hang up reboot procedure.”

 

[hightech-guy]

Could you amplify on your comment regarding the infotainment reset? “…any infotainment issues are solved with the 10 second phone hang up reboot procedure.”

Hold down the call hang-up button on the steering wheel for 10 seconds, and the infotainment system will do a soft reboot. Fixes most temporary fluke software problems that may happen from time-to-time with the infotainment system (lockup, black screen, stuck app, etc).

 

[bharat9569567]

Thank you so much for this guide. This is my fourth time where the car has hit me with many errors upon starting and I cannot shift into any gears "condition to shift not met", along with battery errors and all kind of other errors. I followed your guide to the T, and had no issues pulling the negative wire from the 12V battery and then plugging it back in to see if it did anything. My car still had the same issues/error codes presenting. Are we suppose to charge the 12V battery itself before reconnecting the wire?

I ran to my nearest Canadiant tire store and bought a 12V battery charger, and tried to follow the lyriq user manual where I pulled open the red tab to expose the positive red terminal, and pulled up a GRND labeled cover on the right side to expose the negative terminal. My 12V Battery charger didn't detect any battery connected, and I couldn't get it to charge.

Any luck for me or do I have to get the vehicle towed again?
Unfortunately I'm in Canada so there are no lemon laws, but I am thinking about trading the car back in to the dealership for a XT5. Bummer because I really love this car inside & out.

Appreciate any help from you, thank you!

 

[hightech-guy]

Thank you so much for this guide. This is my fourth time where the car has hit me with many errors upon starting and I cannot shift into any gears "condition to shift not met", along with battery errors and all kind of other errors. I followed your guide to the T, and had no issues pulling the negative wire from the 12V battery and then plugging it back in to see if it did anything. My car still had the same issues/error codes presenting. Are we suppose to charge the 12V battery itself before reconnecting the wire?

I ran to my nearest Canadiant tire store and bought a 12V battery charger, and tried to follow the lyriq user manual where I pulled open the red tab to expose the positive red terminal, and pulled up a GRND labeled cover on the right side to expose the negative terminal. My 12V Battery charger didn't detect any battery connected, and I couldn't get it to charge.

Any luck for me or do I have to get the vehicle towed again?
Unfortunately I'm in Canada so there are no lemon laws, but I am thinking about trading the car back in to the dealership for a XT5. Bummer because I really love this car inside & out.

Appreciate any help from you, thank you!

Well, the 12V disconnect fixes problems where the car just needs a good reset, but if you have more of a permanent fault - it unfortunately won't help there.

Regarding charging the 12V battery, this is probably best covered below. I believe I know what you did wrong. With the battery negative disconnected, you cannot use the GRND jump start terminal. You have to connect the battery charger negative lead direct to the battery negative post, and same for the positive.

It is certainly worth a try to charge up the 12V battery. I'm not sure which faults you have, but perhaps charging it up will get it happy enough to get into gear and drive.

https://www.cadillacforums.com/threads/12v-battery-issue.1134949/page-3#post-18184295