GM Volt Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
1,464 Posts
P0AA6: Hybrid Battery Voltage System Isolation Fault
This DTC will
determine if the
measured
resistance
between the high
voltage bus and
chassis ground
Is too low which
indicates that the
internals of the
battery are no
longer
adequately
isolated from
chassis ground.

P0AB9: Hybrid System Performance
This diagnostic
indicates an
autostart or
autostop attempt
failed.

P0AC4: Hybrid Powertrain Control
Monitors the
HPC MIL request
line

P1E00: Hybrid Powertrain Control Module 2 Requested MIL Illumination
Monitors the
Hybrid
Powertrain
Control Module 2
MIL request line
to determine
when the Hybrid
Powertrain
Control Module 2
has detected a
MIL illuminating
fault.

P1FFF: Usually associated with low coolant level in HV battery reservoir.
 
  • Like
Reactions: jbakerjonathan

·
Registered
Joined
·
27 Posts
Discussion Starter #3
Thank you..the first dealer visit had them telling me the entire battery was bad and needed to be replaced and yet the battery charges, discharges somewhat, and yet these codes keep coming up and they ignored them..
I am going to be going to another dealer Chevrolet directed to and I want as much info as possible to direct them..
It seems like a short or communication error someplace..
The coolant level sensor was just replaced 3 weeks ago and I checked the level and it is full..
But...I have not heard the coolant circulation pump come on at all since all this started back in December ...
But of course the dealers don’t listen ...
 

·
Registered
Joined
·
4 Posts
Thank you..the first dealer visit had them telling me the entire battery was bad and needed to be replaced and yet the battery charges, discharges somewhat, and yet these codes keep coming up and they ignored them..
I am going to be going to another dealer Chevrolet directed to and I want as much info as possible to direct them..
It seems like a short or communication error someplace..
The coolant level sensor was just replaced 3 weeks ago and I checked the level and it is full..
But...I have not heard the coolant circulation pump come on at all since all this started back in December ...
But of course the dealers don’t listen ...
where did you've replace your coolant sensor and how much did it cost you. ?
 

·
Registered
Joined
·
27 Posts
Discussion Starter #6
P0AA6: Hybrid Battery Voltage System Isolation Fault
This DTC will
determine if the
measured
resistance
between the high
voltage bus and
chassis ground
Is too low which
indicates that the
internals of the
battery are no
longer
adequately
isolated from
chassis ground.

P0AB9: Hybrid System Performance
This diagnostic
indicates an
autostart or
autostop attempt
failed.

P0AC4: Hybrid Powertrain Control
Monitors the
HPC MIL request
line

P1E00: Hybrid Powertrain Control Module 2 Requested MIL Illumination
Monitors the
Hybrid
Powertrain
Control Module 2
MIL request line
to determine
when the Hybrid
Powertrain
Control Module 2
has detected a
MIL illuminating
fault.

P1FFF: Usually associated with low coolant level in HV battery reservoir.
So my question, if you know, could these be the symptoms of an ECM failing?
Is there a single item that these faults are all controlled/triggered by?
I’ve had on/off battery usage..mostly off. It’s like the car doesn’t know which source to use or turn on.
The ICE sometimes doesn’t start (usually when cold ) and hence the one error code..but a key off cycle and it will turn on..
When the battery is powering the vehicle, any speed over 60 or trying to merge onto an expressway there is limited torque and the ICE then flips on...never did that before.
The “service high voltage charging system” error is now on (again the codes you saw are why) and just 3 weeks ago the coolant level sensor was replaced as the dealer said it was bad because of the same error..so the coolant is normal (I checked)
But I haven’t heard the coolant pumps run in quite a while so I’m not sure if that is an issue.
Three weeks ago the dealer told me the battery needs replacing and yet it charges to 32 miles and does power the car but not regularly ..I talked to a number of people that work with these batteries and they told me there is no way the battery is causing the issues..
So I’m trying to figure this out before visiting a different dealer ( one Chevy is sending me to see..but they aren’t doing anything else for me)
Thanks
 

·
Registered
Joined
·
1,464 Posts
So my question, if you know, could these be the symptoms of an ECM failing?
Is there a single item that these faults are all controlled/triggered by?
I’ve had on/off battery usage..mostly off. It’s like the car doesn’t know which source to use or turn on.
The ICE sometimes doesn’t start (usually when cold ) and hence the one error code..but a key off cycle and it will turn on..
When the battery is powering the vehicle, any speed over 60 or trying to merge onto an expressway there is limited torque and the ICE then flips on...never did that before.
The “service high voltage charging system” error is now on (again the codes you saw are why) and just 3 weeks ago the coolant level sensor was replaced as the dealer said it was bad because of the same error..so the coolant is normal (I checked)
But I haven’t heard the coolant pumps run in quite a while so I’m not sure if that is an issue.
Three weeks ago the dealer told me the battery needs replacing and yet it charges to 32 miles and does power the car but not regularly ..I talked to a number of people that work with these batteries and they told me there is no way the battery is causing the issues..
So I’m trying to figure this out before visiting a different dealer ( one Chevy is sending me to see..but they aren’t doing anything else for me)
Thanks
I don't know, but I would be most concerned by the battery isolation fault. Somebody may have put the wrong Dex-Cool into the battery coolant reservoir. You must use only DEX-COOL part no. 12378390 in a Volt or any GM EV or PHEV because it is non-conductive.
 
1 - 8 of 8 Posts
Top