Unable to DC fast charge - OK to AC charge - CP_a163

[Jjengering]

Hello,
First post here, although I have been lurking.

Driving a Model 3 SR+ 2021 55kwh LFP.
Over the last few days my car suddenly came up with the error message:
"Unable to DC fast charge - OK to AC charge"
Looking in to the notifications tab on the MCU it comes under the code CP_a163.

Have initially booked in a service appointment with tesla, they called me saying they will remote diagnose it first.
I have googled for the code CP_a163, but I cant see anything for this specific code either on forums or the tesla website.
My hope is it is just a loose cable or the charge port is dirty or worn out, but my real concern is it could be much worse.

I don't know if any of you have watched the youtuber "rich rebuilds" but there is a video of him having a customer where the coolant nipple on the battery pack was damaged by a bit of debris causing a crack and as a result leaking coolant out the pack.
This area seems alarmingly unprotected considering the implications of it getting damaged!
Tesla quoted $16k for a new battery but they managed to tap the hole and use a brass coupler to repair it for $700.

Has anybody come across anything similar or know of a specialist independent in the UK that might be able to fix it if I get the worst news back from tesla.

 

[jdcollins5]

When the car charging system recognizes a DC charging source it bypasses the AC-DC Power Conversion Module and connects the DC directly to the battery. This bypass is performed within the Power Conversion Module. Tesla will need to determine what the problem is and repair if necessary.

It takes a lot more than a “bit of debris” to damage a coolant nipple on the battery. You would have to run over something fairly large to do this. I certainly would not worry about this. 4.5 years and have never had this problem.

 

[en19ma]

I just had this same error pop up this morning. Funny enough, right after I picked up my car from Tesla service to sort out some rattles.

 

[robnz]

What was the result of this? Just had it pop up.

 

[en19ma]

What was the result of this? Just had it pop up.

Tesla replaced the cable, this was the part they supplied. Under warranty

No explanation other than there seems to be multiple variations of this part

 

[robnz]

Mine resolved itself. I took it in for a service anyway and they disassembled and inspected the implicated parts. Claimed it was fine.

Guess what - it's back!

If this keeps happening I'm not sure what to do. It'll be a nightmare owning this vehicle outside of warranty. This will be the third service in 6 months for charging issues.

 

[en19ma]

My car went back in for service today. It’s charging 95% of the time just fine but now I have intermittent stopping and restarting with ‘charge equipment not ready, see manual’ messages.

I did confirm this cable is a later variation as the previous ones were defective (according to the tech)

So my charging issues are also not quite over.

 

[DanChristensen]

Tesla replaced the cable, this was the part they supplied. Under warranty

No explanation other than there seems to be multiple variations of this part

View attachment 910106

Hi, I'm new here. My M3 LR 2021 blinked with this error. Only saw it for a second on the screen. My M3 just passed the vehicle warranty, meaning I only have warranty left on the drivertrain and battery. Can you see how much this repair was?

 

[LiamPope]

Just had this message popped up on mine, too. I've never even used DC charging. Seems people getting this message are getting some charging cable replaced under warranty, so I might try the same!

 

[jqworle]

Just had this message come up today as I was driving, not visited a dc charger in weeks, as I always charge at home. booked in at Tesla Bristol Wednesday through the app

 

[jqworle]

Well thanks tesla, why bother having the app say 29th november then when i ok the estimate of £0 it changes to 4th december.

 

[Steve446]

Hi, I'm new here. My M3 LR 2021 blinked with this error. Only saw it for a second on the screen. My M3 just passed the vehicle warranty, meaning I only have warranty left on the drivertrain and battery. Can you see how much this repair was?

€0 because under guarantee in my cse (happened 2 days ago fixed yesterday). Headline cost in the bill was about €150.

 

[Michal Foksa]

I was getting CP_a163 (particularly CP_a163_coverOpenDcChgBlocked) for couple of months to a point where it got annoying. I decided to find the issue.

I have 2021 Model 3, EU version with 3 phase charger.

TLTR: I solved the issue by fixing charge port safety with zip tie.

The CP_a163 alert description and payload is clear where to search look for the issue:

DC charging is unavailable because the charge port (CP) electronic control unit (ECU) has detected that the high voltage (HV) back cover and/or CP AC charging connector are not present on the back of the CP inlet.

In my case "the high voltage (HV) back cover" was not present.

Charge port safety cap (how "high voltage back cover" is called by Tesla service manual and EPC), when present, closes electric circuit with contacts on charge port back plate. When safety cap is not present CP_a163_coverOpenDcChgBlocked alert is shown.

Charge port safety cap (1516300-00-A) is held by 2 tabs to an intermediate bracket (1553666-00-A) which is held by 3 tabs to third bracket and together they cover HV bus bars.

Issue was that one of 3 tabs on the intermediate bracket (1553666-00-A) was not properly latched.

I believe given enough time play developed over the contacts and circuit continuity was noticed by ECU.

Solution

I could not properly latch the third tab. I did not find obvious reason why, there was no debris on any surface interfacing with each other.

I zip-tied the stack of those 3 orange plastic pieces together.

It is almost a week since then, no alert so far.

BTW: Very helpful was procedure called "Safety Cap - Busbar - Charge Port to HV Battery" in service manual including all safety precautions.

Until next issue …

 

[davewill]

Well thanks tesla, why bother having the app say 29th november then when i ok the estimate of £0 it changes to 4th december.

I have learned not to take the initial service appointment seriously when reporting a problem. They seem to always wait until just a couple days before your appointment to start remote diagnosis, and your appointment almost always gets bumped. Now, when reporting an issue, I always take the soonest appt. After they finish diagnosis and schedule me for real, I can THEN move the appointment to a time that works for me.