Originally Posted by
Kaz-kzukNA1
That's CEL #40, DBW motor circuit or TH butterfly target/actual positon deviation.
It's not conclusive whether this error was stored in the past or indeed happening at the moment.
If the latter case, very likely to be related to the cause of the engine stall.
Voltage reading seemed to be consistent even during cranking so at this stage, I'll leave power supply related cause out of the scope.
Still, from your latest video, whenever the CEL came back On after the light bulb check mode, the engine stalled so there must be a relationship.
Now that you read the code, the next step is to reset the ECU but please don't do it if you are close to the MOT (6 months extension only applies if renewal date before 01/Aug) or away from your home as there is a chance the ECU may not be able to re-learn all of the co-efficient figures if there is a problem (including loose connector, etc) with the DBW.
Please note that the followings are not the standard reset procedure and only applies to your specific situation.
1. In preparation for the reset process, locate the 7.5A CLOCK fuse inside the pentagonal/octagonal black box under the bonnet/hood.
2. Fully warm up the engine.
Just go out for a short driving or combine the process on your return from outing.
3. Before stopping the engine, switch off the A/C, audio head unit, head light, etc.
Basically, create no load condition in preparation for the next fireup.
4. Stop the engine.
5. Remove CLOCK fuse for 10sec and then place it back.
This will erase all of the error codes from any controllers on the car except for the latest one body ABS brain.
6. Turn IGSW into P2 ON and wait for at least 2sec while keeping eye on the CEL.
Do not start the engine and keep no load condition.
Do not touch the TH pedal.
7. If the CEL came back On after 2sec of light bulb check mode, put IGSW back into P0 Off and then back into P2 On. Otherwise, go to step #8.
Repeat this a few times if the CEL doesn't switch itself Off after every bulb check mode.
This is just to simulate some of your video as the engine always stalled if cranked with the CEL On but then if power cycled, the CEL switched itself Off after the bulb check mode and the following engine fireup was fine.
8. Now start the engine without touching the TH pedal and keep no load condition.
On first attempt, if the engine stalled like before because the CEL stayed On in step #7, go back to P0 and re-start the engine again.
9. Keep running the engine under no load condition and without touching the TH peal for 10 - 15min.
Don't worry about the electrical load increase because of the radiator fan.
10. Stop the engine, wait for a few sec, put IGSW into P2 On and wait for at least 2sec.
11. If CEL came back On after 2sec, repeat #7 and #8 but no need keep running the engine for 10 - 15min. Just short fireup like 10sec is enough.
If CEL stayed Off after 2sec, just start the engine for about 10sec.
Unlike in step #8, the engine rpm should drop to 800rpm almost immediately after the fireup.
12. Stop the engine.
13. Read error code.
If new code or CEL #40 stored, you will need further diagnosis but most likely, loose connector, etc.
14. If no code stored, go out for several outings and remember to read the error code at some point even if you didn't trigger the CEL.
From now on, try waiting for at least 2sec after every IGSW P2 and keep eye on CEL.
On first occurrence of CEL coming back On after 2sec, ideally, do not start the engine and read the error code immediately.
Kaz