No READY. P1A15 error. Condenser charge timeout.

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kiev said:
Simon (username: DBMandrake) is the smartest guy in Scotland for solving problems and he knows how to open a pack and change cells because he did it. There is an EV forum at SpeakEV with lots of UK and EU folks, that may be able to help you find somebody local.
I'm flattered. :oops: I saw civjdh's post on SpeakEV but after a few days nobody else had replied to it as there's really only 2 or 3 of us on that forum who have experience fixing these cars and I don't think any of us has dealt with P1A15. (I certainly haven't)

I've done a cell swap on my car, also an onboard charger repair (as you know) and more recently had to replace a failed vacuum pump with a modified after market one, however after the second major failure in 6 months and looming rust underneath and on brake pipes (enough for an MOT test warning) I'd had enough so I traded my Ion in on a 2016 Leaf before something else went wrong! That's why I haven't been poking my nose in here much lately.

I'm only about 30 miles from civjd and would normally try to give a bit of help unfortunately Coronavirus is really blowing up here again and we're actually going into a 2 week partial lockdown tonight where we're not even supposed to be driving between different council areas for anything other than work. Crazy times, and not a good time to be repairing a problematic car - another reason why I took the jump and traded the Ion in for something a bit newer and (hopefully) more reliable as the onboard charger failure happened only 3 weeks before the nationwide 6 month lockdown we had - quite a close call. I could have been without a working car for a long time had it failed a few weeks later.
i hope the Laef works out well for you, they are nice cars--almost luxury compared to the triples. i fixed one up for my daughter and she is loving it.

Take care, let's hope we can all survive this virus and lockdown mess.
kiev said:
i hope the Laef works out well for you, they are nice cars--almost luxury compared to the triples. i fixed one up for my daughter and she is loving it.

Take care, let's hope we can all survive this virus and lockdown mess.

Yeah there's a lot to like about a 30kWh Leaf, it does Kinda feel like luxury compared to the Ion, especially in the heating and insulation department. :) The doors all have a thick layer of carpet underfelt behind the door cards and it seems to be draught free as well making it feel warm and cosy, and once warmed up (or preheated) the heater is just ticking over unless its near freezing outside. On top of that the heat pump and instant heat ceramic PTC heater means it can put out a lot of heat quickly without much power. Timed plugged in preheat is luxury in cold weather too, and remote preheat via the smartphone app is nice when not plugged in. (As the timer only works plugged in)

Probably the biggest disappointment with the Leaf for me is the Leather seats while more comfortable than the park bench seats in the Ion (which were extremely uncomfortable for me even with a seat cover) still aren't very comfortable as they're somewhat hard and the side bolsters in the base are hard, pointy and too close together and nip into the side of your legs, so I've been experimenting with different seat covers to mitigate that.

But other than that it's going really well. Summer range in my Ion was down to 50-55 miles and 30-35 miles in winter. On the same commute I was getting 107 miles range on the Leaf back in warm July weather and am still getting around 90 miles in near freezing (0C) conditions last week, so nearly 3x the winter range of the Ion - and that's with the heater turned up to a warm toasty 22C vs using bare minimum heater in the Ion and layers of warm clothes..
kiev said:
Yes it does go to the bottom of the lower right corner of Lic's photo, to Connector CN4, labelled "VDC". The red and blue wires are from the (+) side of the pack and route to pins 1 and 2; the white wire is from the (-) side of the pack and routes to pin 5.

CN4p1 then routes to CN5p1, labelled "VDC-R", which is a red wire running to the large silver-colored resistor on the heatsink, ~50W power resistor, 510 Ohms. The other end runs back to CN5p5, thru a white wire. This is the quick bleed resistor for the large "condenser", the big black 800 uF capacitor in the top plenum. CN5p5 routes to the Drain of the big FET2; the gate is driven by the output of optocoupler PC7; and the Source is connected to pack (-) thru CN4p5. This RC combination has a time constant of about 0.4 seconds and would drain the big cap in about 1.2 seconds.

In parallel from CN4p1 is a voltage sensing circuit running from CN4p1 to a series string of six 100k resistors and a 6.8k that route to the hybrid chip board pin 1 labelled "VH" with the return on pin 2 labelled "VI", that connects back to pack (-) thru CN4p5. This is a voltage divider to drop the high voltage down by a factor of ~90: for 360 Volts at the condenser, the voltage at the Hybrid is about 4 Volts.

If any portion of that sense hybrid circuitry were not working properly, then it may be that the HV is not reading properly.

Your test to remove the jumper wires at the pack buss bars seems to indicate a problem down below on the main board in the bottom plenum of the MCU. Did the car go to READY when you ran that test? i would guess not, but you did prove that the bottom circuit is pulling down the pack voltage at the "condensor" and throwing the P1A15 DTC.

[edit: corrected some hasty notes from yesterday and added details of voltage divider and fast bleed resistor; and sketch of circuit]

sketch of circuit

Hello to everyone,

Sorry Kiev, are you sure about the value of the 3 small capacitors in parallel? Just 5 pF each or 390nF like the French guy mentioned?
(C227, C229 and C231 surface mount capacitors as 390 nF). Thanks a lot and this forum is formed by great people!
Thank you for looking at this in detail, it's always good to have someone else to check the drawings.

My finding was from a measurement on the board using smart tweezers; with all the parallel paths it is not likely an accurate value.

i haven't removed any parts to measure separately, but for sure i would be happy to change the values to a better measurement. 3 parallel 390nF gives nearly 1uF, so that is likely the design target and the three were used to provide some redundancy?
kiev said:
Thank you for looking at this in detail, it's always good to have someone else to check the drawings.

My finding was from a measurement on the board using smart tweezers; with all the parallel paths it is not likely an accurate value.

i haven't removed any parts to measure separately, but for sure i would be happy to change the values to a better measurement. 3 parallel 390nF gives nearly 1uF, so that is likely the design target and the three were used to provide some redundancy?

Thank you Kiev,

Yes I also think the target design was for 1 micro F and there are 3 of them in parallel for some redundancy. However I would have use more serious capacitors for such delicate detection circuit :) The problem as you know is that disconnecting such small capacitors for measuring we likely damage them.
In near future I will should a chance to measure something on that board and I report the results, but it will be an iOn not an iMiev.
Hi everyone, I've just bought a 2012 Peugeot Ion as a non runner. Must start off by saying the forum has been very informative and I certainly understand the car a lot better now.

I've downloaded Hobdrive and used my elm327 obd adapter to read the fault codes. This has come up with P1A15. From reading previous posts I understand this relates to the car detecting a difference between the battery pack voltage and the capacitor voltage (the big black meiden one?). I'll attach the Hobdrive screenshots ASAP (these show that the capacitor is only at 2v).

If I reset the DTCs using Hobdrive, I do (occasionally) hear the contactors moving into position. I've only managed to get this to happen a couple of times though, as the DTC reappears very quickly. The rest of the time it's completely silent.

Have read from the previous posts that this issued may be due to some failed components on the PCB on the inverter. I'd really appreciate the group's thoughts on likely culprits- appreciate that this has probably been covered in previous posts, but I'm a bit of an EV novice (my LEAF hasn't needed anything done so far!)

Thanks Jason

Hi there, another P1A15 failure on a 2017 CZero. At first I could clear the DTC using Hobdrive but now is a very rare thing to be able to get Ready (possibly not at all). I have found a NHTSA hosted troubleshooting guide, there's a lot of steps involved.
Hope to catch some transient voltage traces with oscilloscope. Just now waiting on some safety equipment so I can remove service plug on traction battery, Will keep you posted
Hi all, update on the troubleshooting for a P1A15 code error.

I have checked the coil resistance of the 3 traction battery pack contactors (negative, precharge, mainpositive). All three coil resistances measured 33ohm.

Is this a typical or good reading?
It has at least proved that none of the contactor coils or their supply circuits are open circuit.

Method used to measure the resistance of the contactor coil was to unplug the relevant plug from the EVECU (under rear seat) and measure red wire resistance to ground, yellow wire resistance to ground, violet wire resistance to ground for precharge, main positive, negative contactors respectively.

Since I no longer hear any clacking of these contactors when going into ready, my proposed next step in the trouble shooting is to energise the coils on these contactors one at a time and listen for the clatter. Question, should I do this with the service plug retracted in case one of these contactors is stuck closed?

Many thanks
From the battery service manual, coil resistance for positive and negative main traction battery contactors should be 33-39 ohms at 23 degrees C. I measured at about 3 degrees C.
What is the open circuit voltage reading of your 12V aux battery? What are the reading when the key is turned to ACC and ON and START positions?

This DTC code can be commonly caused by a weak, worn or old aux battery, so this must be ruled out before digging into the contactors. It is not a good idea to energize the contactors, there are large capacitors on the HV buss that can cause high inrush currents that will damage the precious metal points of the contactors.
With the Manual Service Disconnect plug removed, there should not be any be any circuit that would allow the HV bus capacitance to be charged, other than the high impedance of the test lead/meter. The impedance of the test lead and meter is 5MOhms 15pF so not anticipating any contactor damage. Let me know if there is a flaw in this approach.

I have tried testing with the one month old auxiliary battery charged up to 12.9 volts with the key off, 12.7 volts at the EVECU according to HOBDRIVE. I'm going to use a large external 60Ah battery for testing going forwards and will confirm voltage levels throughout the 12v with Fluke recorder.
Good news on the 12V aux.

Are you able to read DTCs--are there any other than the P1A15?

There are codes related to the main contactors which would likely get thrown if they were faulty.

If you pull the seat to get to the main disconnect sometimes the airbag DTC gets set. Those folks that have done this can reply if the car will run with SRS codes, seems that only dealer tool can reset SRS.

i can't remember anyone having a faulty main contactor, but if this car is new to you and unknown previous history, and possibly not running when you got it, then checking the main contactors as you have described will help to rule them out as culprits. Also most of us here have very little to no experience with the 2017 model, which could have different circuitry, DTCs, control logic, etc.

Will the car charge? Is the 20A fuse in the MCU okay?
Hi Kiev,

Car was purchased new by me so I have all the history.

When the problem started back December last year, I connected up Citroen/Peugeot Diagbox tool (offline version) and read all the ECUs. Only DTCs were P1A15 and U1113. The car has always had U1113, there is a note in Diagbox to ignore this code.

I suspect something on the EVECU or upstream of the EVECU: the reason being the I can't hear any clacks from the contactors (after clearing DTCs)

My approach will be to confirm that the contactors actual energise (proving traction battery pack precharge resistor, HV wiring to MCU-Inverter, HV battery pack main fuse. Then I will record the C105, C106, C107 ECU outputs on a start and see which if any are energised.

If the negative contactor and precharge contactor do NOT energise, the problem is definitely in the EVECU or upstream. If they do, but the positive contactor does not energise, its time to isolate the heater, aircon and OBC in case of HV fault leakage. If the car still does not go into ready (still does not energise the positive main contactor), its time to start measuring the "condensor" voltage rise and compare a directly measured value with the value the EVECU is reporting.

Thats the general approach, any advice much appreciated
In the UK Citroen offered 3 years warranty in the car and possibly 8 years on the battery. But I would like to know what component is faulty before entering the warranty rabbit hole.
Another I've just checked is fuse number 4 from the fusebox by drivers right foot RHD cars. This fuse is described as a "starter" fuse and provides power to the EVECU. Anyhow it was good : another thing checked off.
Hi a small update, heavy snow here so not ideal for doing any testing on the HV side of things.

On the low voltage, I've removed and checked the permanent supply fuse to the EVECU (this is actually the interior courtesy light supply fuse). Also the Supervisory Controller supply fuse (this is the ignition switched supply to the EVECU). I had a theory that there was a bad connection in the 12v supply to the EVECU. So I hooked up a 2 channel scope to the 12v auxillary battey (Channel A) and the 3rd pin on the EVECU, light geen wire 36V connector (Channel B). Static voltages were about 12.1v on the 12v battery, about 11.9v on the EVECU switched supply. When I switched to "start", voltages dropped and the lowest seen at EVECU switched supply was 10.73 volts with coincident 11.84 at the 12v auxillary battery positive terminal. There was a bit of clunking coming from the contactors I had set the sampling time on the scope at 50ms but with a bit more reading up on various DC high voltage contactors, have learnt that these operate typically at timescales less than 25ms including bounce. So next time will sample at 10ms.

So I've now convinced myself to try the same measurement but with a different newer bigger auxillary battery, just to rule out any 12v supply issues.

If this does not make any difference, next move will be disconnect PTC heater and AC compressor, as already suggested.