How to Replace a Faulty High Voltage Warning System in Your EV
Service High Voltage System Warning
#1 (Edited)
I've only had the vehicle a few weeks now. Came with a full main dealer service history (apart from last service, independent). The car would not accept a charge this afternoon, engine management light is on, plus Service High Voltage System warning on the dash. When I plug in the granny charger the amber/orange light on the dash stays on, no green lights or horn beep.
Is there anything that I can try, before having to take it to a dealer?I have tried using a different plug socket, opening closing the socket door several times using the remote or button in the vehicle. The socket in the car looks dry, no signs of any damp etc.
Since owning, I have managed to free off both the door mirrors which were seized. Fitted a new lower front bumper trim (smaller profile one), added mesh to the lower bumper & spent numerous hours cleaning & polishing it.
I am truly gutted & feel sick. The car is excellent, lovely to drive & incredibly economical. I purchased it private sale, so there's nothing I can do about that side of things.
UpdateCars in the dealer. They have diagnosed a faulty battery system coolant sensor, plus 2 system updates. Only problem is that there are no coolant sensors in the country. So going to have to wait a week. I'm looking on the positive side, it's a simple fix & not too pricey. They did a health check on the rest of the car & all good apart from the fluid in the puncture repair kit needs replacing. So far the dealer has been great, I'm just looking forward to getting the car back
Further Update Happy to say that the car is back from the dealer. It got a clean bill of health, new sensor fitted & 2 software updates.Charging & driving lovely.
Thanks for all the messages & suggestions
See less See more #2it's most likley a problem with the Granny charger rather than the Ampera, the two hve to communicate to start the charging process.look up the J1772 protocol for how that works. practically there are two things you can do.1/ clean the socket connections with contact cleaner or alcohol to see if it's just dirty2/ go to a public charger that supports J1772 ( see zap map for locations) if the Ampera charges there then the granny is faulty.
#3Just a further thought you need to read the OBDII codes for which you need a ODB connector and an application like torque pro see other service HVS threads on this site
#4Codes. We need codes. It is very common issue otherwise. Usually it is flaky level sensor for battery coolant reservoir. If it triggers, you must reflash the HPCM2 module to release it (which is usually done at the dealer, but can be done at home if you have correct tools).Pop the hood, check if level in battery coolant reservoir is OK. If yes, get a good error reader and take out error codes. They will most likely be P1E00, P1FFF and P0AA6. If yes, you need a software update,
#5Just to note that I had the SHVCS warning come up and changed the coolant sensor for a resistor instead, but still keep getting the error from time-to-time, BUT ... I can clear the faults (P0AA6, P1F0E, P1FFF etc.) using Torque Pro on Android with a cheap ELM bluetooth OBD dongle. So, it's clearly not always the dodgy sensor that triggers this problem, and it is possible (at least in my case - and several times) to clear the faults and charge as normal, without needing a dealer visit. Hope that helps.
#6If fault reappears again after fitting resistor, it is probably dodgy connection. Sensor cable is grafted to cable couple dm lower down. The bodge is under insulation tape. If this corrodes, you will still experience bad connection despite fitting resistor further up. In that case, you have to unwind the splice and solder resistor lower down.
#8Thanks for the advice, but the sensor cable bodge is (I believe) specific to the early 2011/2012 models, and I have a 2013 model Ampera which I think had a new wiring loom to include the battery coolant level sensor. I'll take another look, but at the moment I just keep the ELM bluetooth OBD in the car
#7This the very best explanation of what issues are and how to mitigate them:
#14Nah, they will:
- Check coolant level, find it OK
- Read out error codes, find same codes as you did
- Lift the car, remove battery leak plug. Find out that nothing is leaking
- Try to fit the plug back, if it is broken, backorder new one (might take a week or two)
- Reflash HPCM2 and BECM, erase codes
- Bill you between 300 and 700 EUR in GBP.
- (Optional) try to sell you some other stuff like filters, replacing belts etc.
So i need to sell my GM VCX Nano on here or Ebay as i was unable to ever get the AC Delco TDS portal to accept payment via cards from the UK, and no help from ACD. So i gave up. My Chevy Volt went into UK "Bellingers" dealer (Vauxhall and ex-Chevy UK dealer) yesterday, collected it today. Despite them selling me a new coolant level sensor last August, and fitting it 1st October 2020 (less than 12 months) they refused to "honour" clearing the returned latched SHVS error under claim of this repair. They "insisted" of doing a system investigation, found zero hardware faults and just error codes P1E00 and P0AA6. They "fixed" it by reflashing the HPCM2 and BECM software (as they did in the 2020 repair) , charged and discharged the battery twice, and charged me 103.60 for the pleasure. On the drive home i used all the charge and have 9.4kw of the 2014-2019 10.1kw capacity useable, but this was also the case after the repair in 2020.WOTS type defeat plug was ordered from USA last week! So annoyed i couldn't buy the 35 2 hour SPS programming slot off AC Delco from the UK and do it myself. Will fit the defeat plug as soon as it arrives from the USA, and from next Tuesday the Volt is being relegated to 2nd car with the arrival of a Peugeot E-208 GT until November (ONTO) and then a Tesla Model 3 LR from November. Full retirement in 2022 when I can take delivery of a Tesla Model Y LR in the UK RHD. Then the Volt is going into storage as a future classic after some cosmetic touch ups, and only used as a "backup" car if Either Tesla is off the road without replacement provided.
#16Sorry to hear that it did not work. Maybe you could try PSA site and just enter your VIN? I had no issues with
Service Box(but I have an Ampera, not Volt). Reflashing was done in 10 minutes. At least Bellingers charged reasonable amount of money ... here in Sweden they would just tick the list and bill at least 500 for that.
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[SOLVED] P0A0A Code: High Voltage System Interlock Circuit Diagnosis And Fix
The automobile fault code P0A0A indicates a problem with the High Voltage System Interlock. This can be identified by the Engine Light or Service Engine Soon Warning Light turning on. The cause of this fault code could be a faulty High Voltage System Interlock, an open or shorted harness, or a poor electrical connection in the circuit.
To fix this issue, it is recommended to visually inspect the wiring harness and connectors for any damage. Look out for broken, bent, pushed out, or corroded pins in the connectors. The repair time for this fault code is estimated to be around 1.0.
It is important to address this issue promptly to ensure the proper functioning of the high voltage system.
| Repair Importance Level | 10.0 (Out of 10) |
| Estimated Repair Time | Approximately 1.0 hour |
| Repair Difficulty Level | 10.0 (Out of 10) |
Unveiling The Mystery: Symptoms Of Fault Code P0A0A Revealed!
When the engine light is on or the service engine soon warning light is illuminated, it could be a sign of the p0a0a fault code.
- The symptoms of the automobile fault code p0a0a include the Engine Light being ON or the Service Engine Soon Warning Light being illuminated.
Unveiling The Culprits: Code P0A0A Possible Causes Revealed!
The automobile fault code p0a0a can be caused by a faulty high voltage system interlock, an open or shorted interlock harness, or a poor electrical connection in the interlock circuit.
- The fault code p0a0a can be caused by the following:1.
- Faulty High Voltage System Interlock.
- 2.
- High Voltage System Interlock harness is open or shorted.
- 3.
- High Voltage System Interlock circuit has a poor electrical connection.
Fixing Code P0A0A: Simple Steps To Resolve The Issue
To fix the p0a0a fault code, start by visually inspecting the wiring harness, connectors, and components for any damage or corrosion.
- To fix the automobile fault code p0a0a, start by checking the possible causes mentioned above.
- Then, visually inspect the wiring harness and connectors related to the issue.
- Look for any damaged components and check for broken, bent, pushed out, or corroded connector pins.
- This fix is estimated to take approximately 1.0 hour.
Cracking The Code: P0A0A Cost And Complexity Unveiled!
The factors influencing the cost of diagnosing and fixing the automobile fault code p0a0a include the estimated repair time of 1.0 hour.
Auto repair shops typically charge between $75 and $150 per hour for their services.
P0A0A Fault Code: Understanding The Description And Implications
The P0A0A fault code is related to the High Voltage System Interlock Circuit in an automobile. This code is a Diagnostic Trouble Code (DTC) that monitors the sensed voltage when the command voltage is high. Its purpose is to determine if there is a fault in the circuit.
When this fault code appears, it indicates that there may be an issue with the interlock circuit in the high voltage system of the vehicle.
The interlock circuit is responsible for ensuring the safe operation of the high voltage system, which is crucial for the functioning of hybrid or electric vehicles. If you encounter the P0A0A fault code, it is important to have it diagnosed and repaired promptly. Ignoring this code can lead to potential safety hazards and may affect the performance and efficiency of the high voltage system in your automobile.
Seeking professional assistance from a qualified technician is recommended to properly diagnose and fix the issue.
FAQ
What are the possible causes for the automobile fault code p0a0a?If you see the engine light or service engine soon warning light on, the fault code P0A0A could be the culprit. This code is often caused by a faulty high voltage system interlock or issues with the interlock harness. It could also be due to a poor electrical connection in the high voltage system interlock circuit. To fix this, visually inspect the wiring harness and connectors, checking for any damage or corrosion. Additionally, look out for broken, bent, pushed out, or corroded connector pins.
How can I visually inspect the wiring harness and connectors to fix the p0a0a fault code?If youre dealing with the p0a0a fault code and your engine light is on, its time to take a closer look at the wiring harness and connectors. The cause could be a faulty high voltage system interlock or an open or shorted interlock harness. To fix it, visually inspect the wiring harness and connectors for any signs of damage. Check for broken, bent, pushed out, or corroded pins on the connectors. Dont forget to also check for any damaged components.
What should I look for when checking for damaged components and connectors pins to resolve the p0a0a fault code?When resolving the p0a0a fault code, start by checking for damaged components and connectors pins. This can be done by visually inspecting the related wiring harness and connectors. Look for any signs of damage such as broken, bent, pushed out, or corroded pins. These issues can cause a poor electrical connection in the High Voltage System Interlock circuit, leading to the engine light being ON. By addressing these potential causes, you can effectively fix the problem.
Wrap Up
If your engine light is on and youre seeing the P0A0A fault code, it could be due to a faulty high voltage system interlock or issues with the interlock harness. To fix it, visually inspect the wiring harness and connectors, checking for any damage or corrosion. Look out for broken or bent pins on the connectors.
