Dead C-zero after only 6 years and 21k miles :(

[samlivingstone]

My C-zero - six years old, 21k miles, full service history - has just died: the garage has said that we either need to replace the Compressor (part number 1611 082 480) or the Water heater (part number 1609 720 680) - these either heat or cool the battery, they are not the heater or AC for the cabin - and that replacing one of these parts will then cost about £4000- what the car is worth.
Major intake of breath - it's not the battery or the motor, its only the bits that keep the battery at the right temperature, so why would they need to be that expensive!
Keen to know if this is spurious / wrong (that there is something else cheaper to fix that has broken that our 'we don't see many of these sir' Citroen / Mitsubishi garage is not aware of), if there is a cheaper source of parts (how can these parts be so expensive...?!) or any other related learning from those who have been here before; seams crazy that this car is potentially writing itself off.
Thanks in advance.

 

[kiev]

Did the mechanics use a MUT 3 tool (or the Citrogen equivalent) to diagnose the problems? If so what were the diagnostic trouble codes did they read that were stored in the EV-ECU?

i don't know about the C-zero in detail, but i would think it similar to the i_Miev. Those two high voltage loads (heater and compressor) have connectors which can be opened to isolate them from the battery pack. If those devices were broken or the cause of the issue, then the car should go to READY when disconnected.

The Chademo charging function requires the air conditioning compressor in order to cool the battery pack, but regular charging should work without the compressor.

i'm not aware that the heater is required for the battery pack.

[edit]
With such low mileage--do you know if the 12V Aux battery is the original one of the car from new, or has it been replaced? A weak, worn out and old 12V battery will cause issues with the operation of the High Voltage systems such as you have experienced. In some cases just replacing the 12V has solved the issues.

 

[samlivingstone]

Kenny, thanks for your reply; much appreciated.

Did the mechanics use a MUT 3 tool (or the Citrogen equivalent) to diagnose the problems? If so what were the diagnostic trouble codes did they

read that were stored in the EV-ECU?
Not sure, will find out and get back to you.

i don't know about the C-zero in detail, but i would think it similar to the i_Miev.
Its the same car with a different badge, expect technically identical.

Those two high voltage loads (heater and compressor) have connectors which can be opened to isolate them from the battery pack. If those devices were broken or the cause of the issue, then the car should go to READY when disconnected.
Useful to know, will see if the garage can ascertain if there are broken.

The Chademo charging function requires the air conditioning compressor in order to cool the battery pack, but regular charging should work without the compressor.
Interesting; every time the car is plugged in a battery fan whirs into action and we use the regular (old / slow / low power) UK, not the Chademo.

i'm not aware that the heater is required for the battery pack.
Okay, think you know this better than me - useful to know.

[edit]
With such low mileage--do you know if the 12V Aux battery is the original one of the car from new, or has it been replaced? A weak, worn out and old 12V battery will cause issues with the operation of the High Voltage systems such as you have experienced. In some cases just replacing the 12V has solved the issues.
Thanks - my first response to the car fail was to trickle charge that battery, but I confess I don't know how old it is / likely its original. I will ask the garage to switch it out for a fresh one...

 

[kiev]

i would recommend you replace the 12V if it is old, weak or worn out; then disconnect the A/C compressor and heater connections and see it the car will start, i.e. go to READY.

If the heater or compressor were shorted internally somehow, then they might be adding too much load such that the car won't start, so disconnect to take them out of the picture...

 

[PV1]

I'll second the 12 volt battery replacement. Be really careful if you mess with the heater/AC power connectors. 360 volts is nothing to be careless with. My guess is that the A/C compressor has an internal short or is trying to run while the car is powering up. Both would cause a drain on the high voltage bus and prevent the car from going READY.

The cabin HVAC system is shared with the battery, so both the heater and A/C can be directed to the battery. The heater is primarily for really low temperature charging. The car will warm the battery up a bit before charging to minimize lithium plating. I've rarely noticed my car doing this, though.

The A/C is used for cabin cooling as well as during quick charging to keep the battery cool. The compressor only becomes active if a cell temperature sensor reads 31 C or higher. If the pack is colder than that, then only the fans will run.

 

[samlivingstone]

So, just had this reply from the Citroen / Mitsubishi dealership who have my 'dead' C-Zero:

We have carried out a battery check to the 12v battery and it is fine.
The dtc code extracted is P1A15 Capacitor action Failure.
I also appreciate, the repairs equals the value of the vehicle and that we cannot guarantee, if the repairs are completed , that this will cure the fault.

Any views on next steps I might best take gratefully received !

 

[kiev]

Did they test the 12V aux battery under load according to the method of the Factory Service Manual, FSM? Just putting a voltmeter to it won't reveal the condition. Have a look at post #2 of the OBC troubleshooting thread for information about testing the 12V aux, http://myimiev.com/forum/viewtopic.php?f=23&t=4079

i had this code before and it went away after replacing the 12V aux.

Below is a link to a thread of another member with this DTC, this post has the steps in the P1A15 troubleshooting. There is nothing in the FSM about this DTC that indicates to replace the A/C or heater, so it is quite puzzling how your mechanic reached that solution.

When the key goes to start there are numerous relays and contactors that engage in a sequence to bring the high voltage up in a controlled manner. The voltage is being monitored and if it doesn't reach certain levels within a prescribed time period, then this and/or some other DTCs will be set to indicate the problem; in your case it is the voltage of the big capacitor within the Motor Control Unit, MCU aka inverter, that is slow to come up to HV.

http://myimiev.com/forum/viewtopic.php?p=26317#p26317

 

[phb10186]

Did they test the 12V aux battery under load according to the method of the Factory Service Manual, FSM? Just putting a voltmeter to it won't reveal the condition. Have a look at post #2 of the OBC troubleshooting thread for information about testing the 12V aux, http://myimiev.com/forum/viewtopic.php?f=23&t=4079

i had this code before and it went away after replacing the 12V aux.

Below is a link to a thread of another member with this DTC, this post has the steps in the P1A15 troubleshooting. There is nothing in the FSM about this DTC that indicates to replace the A/C or heater, so it is quite puzzling how your mechanic reached that solution.

When the key goes to start there are numerous relays and contactors that engage in a sequence to bring the high voltage up in a controlled manner. The voltage is being monitored and if it doesn't reach certain levels within a prescribed time period, then this and/or some other DTCs will be set to indicate the problem; in your case it is the voltage of the big capacitor within the Motor Control Unit, MCU aka inverter, that is slow to come up to HV.

http://myimiev.com/forum/viewtopic.php?p=26317#p26317

... and if that's the original 12v battery, even more reason to just try a new one.

 

[Gary12345]

Depends how electrically confident you are, but it would be worth checking the components in the motor control unit, particularly for capacitor failure.

Whereabouts in the UK are you located?

Thanks.