think 2009

[jonandse]

Hello all, still no workshop access so haven't been able to access the battery yet. Had a closer look in Zebra monitor now and this screen caught my attention: the Zebra does not get AC in.

However according to Orla's diagvga.bas the PCU reads a fine 231VAC in so I assume the EVSE should be okay.

I measure line voltage in the round AC connector on top of the Zebra BMI.

Any advice?

If anyone has a spare BMI please let me know.

[pexic]

Hi
I think you should disassemble the BMI and check inside for defective parts.

[jur]

Hej,

I thought so, too, but: I have just witnessed the BMI of my battery _intentionally_ switching its internal AC supply off and on while in balancing mode. The status display in ZebraMonitor looked exactly the same.
So I would check first if this state persists, and check also the "AC switch" and "AC relay" status as well as the "diagnostic faults" and "last 20 errors" pages to get the bigger picture.

btw.: my battery (and car) is up and running again, albeit with a non-working dc heater, which is a bit of a pain to manage.

Rgds, Jens   

[jonandse]

Hi all, rain is pouring down outside but the car is in the workshop! Battery on its way out!

Of course the Think is parked on the red carpet!

[jonandse]

AC heater element is 84 ohms.
Pack voltage is 304V.
Pack is cold.
BMI zebra monitor says only a few volt but maybe that's because the contactors aren't engaged until proper temp is reached?

[pexic]

I don't have zebra but I suspect you can easily find the answer but start heating the battery   good luck and keep us posted.

[jonandse]

The BMI was a complex creature. An Infineon C167 processor and external 28F4000 parallel flash. Loads of components - and glue. Probably chosen for its measurement and control history and CAN interface.

I focused on the AC heater parts. As Orla wrote already 5 years ago (in this thread: https://elbilforum.no/index.php?topic=30613.15) the AC heater in the battery is connected to the AC in through both a mechanical relay and what is probably a triac in a TO220 package. This triac's gate is connected to a DIP package which I would again guess to be an optocoupler/optotriac but it is really hard to see in all the glue and with all the cables.

I soldered in some measurement wires, put everything back on and plugged it all in to the battery again. Measurements revealed the mech relay is never engaged and in Zebra monitor I can read "AC voltage present: false" so I guess I have the same erratic AC detection problems that Orla had 5 years ago.

I guess the next step is to tear down the BMI into atoms to see if the AC detection circuitry can be understood and repaired.

If anyone has a spare BMI I would be happy to buy it, please PM me.

[Orla Pedersen]

AC heater element is 84 ohms.
Pack voltage is 304V.
Pack is cold.
BMI zebra monitor says only a few volt but maybe that's because the contactors aren't engaged until proper temp is reached?

Don't ever load a cold zebra-battery, that includes instruments, that's why the BMI disconnects voltage messurements when cold. Any load will destroy the chemestry.

[jonandse]

Thanks for the advice Orla, I only measured it with a DMM for a few seconds so hopefully no harm was done.

Did you ever solve the BMI AC detection issue you had in 2016?

Seems there is a diode bridge and a blue transformer circuitry providing this info to the C167 processor.

[Orla Pedersen]

Did you ever solve the BMI AC detection issue you had in 2016?

No, before i got the battery out off the car it "exploded" leaving acid dust all over the place, and inside the BMI. These battery's are old and unsafe in my view.

[jonandse]

The primary winding was broken on the blue transformer. Replaced it.

I agree that the best-before date on the Zebras are due. However this battery is almost rust free and has been cold since 2016 so I'll take the risk (outdoor!) and try to get it going - at least so I can log some traffic when it works.

[jonandse]

Changing the transformer fixed the AC detect problem!

Now the heating works.

Time to get the battery back the car!

[jonandse]

The car runs and today it drove out from the workshop!

The gear selector seems a bit misaligned, I have to hold the gear selector towards E to make it think it is in D mode. All other gears are ok, P, R, N works but D mechanically indicated N on the gear indicator and nothing happens until I gently press the gear selector towards E. E also works as intended so the car is functional but this will fail the EU-inspection so I have to get it fixed to make the car road legal.

Any advice?

[pexic]

Dismount and clean the electric multi-contactor connected to the gear selector.

[jonandse]

Unfortunately it was a mechanical failure, the roller part that keep the gear selection steady has snapped off. Any clue if this part is available on any other car? Ford, Peugeot, Citroën...