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Old 3rd December 2018, 20:22   #11
SD1too
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Originally Posted by Alexandru.Edward View Post
... and the HRW not working.
I read that can be from ECU CANBUS.
I'd be surprised if the HRW has anything to do with the CAN bus.
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Originally Posted by COLVERT View Post
Try a GOOD battery. You might just have a pleasant surprise.
Low voltages can do silly things.---


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Old 3rd December 2018, 21:05   #12
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Originally Posted by SD1too View Post
I'd be surprised if the HRW has anything to do with the CAN bus.



Simon
Well I can assure you Simon, that in this case you are completely and utterly wrong

The actual fault is described as "CANBUS Messages Failure Instrument Pack 3" by T4, and the symptoms are specifically no rev counter, temperature gauge, or heated rear window.

It is not caused by low battery voltage, a spike, or indeed anything other than an internal failure of one specific IC on the DDE4, and replacing the battery, charging it up, disconnecting it for a while is going to do absolutely nothing

If you wish to try this out, unplug your instrument pack, then see if it is possible to activate the heated rear window

Brian

P.S. almost every DDE4 with this defect is from an age range encompassing VIN 1M, and rarely if ever are these units ever water damaged.

I tend to use them as donor units for conversion of NNN100693 ECM units to make them into NNN100692SR

Last edited by marinabrian; 3rd December 2018 at 21:17.. Reason: added post script
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Old 4th December 2018, 12:20   #13
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Originally Posted by marinabrian View Post
Well I can assure you Simon, that in this case you are completely and utterly wrong

The actual fault is described as "CANBUS Messages Failure Instrument Pack 3" by T4, and the symptoms are specifically no rev counter, temperature gauge, or heated rear window.

It is not caused by low battery voltage, a spike, or indeed anything other than an internal failure of one specific IC on the DDE4, and replacing the battery, charging it up, disconnecting it for a while is going to do absolutely nothing

If you wish to try this out, unplug your instrument pack, then see if it is possible to activate the heated rear window

Brian

P.S. almost every DDE4 with this defect is from an age range encompassing VIN 1M, and rarely if ever are these units ever water damaged.

I tend to use them as donor units for conversion of NNN100693 ECM units to make them into NNN100692SR
Brian.---If this should prove to be the case can that IC just be replaced to cure the problem ???


PS. Cor, you did hammer poor old Simon a bit.----He didn't seem to be specific. Just that he would be SURPRISED if the heated rear window was involved.

PPS. Couldn't you see your way to just letting him be SURPRISED and not totally wrong.----------------------------------------
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Old 4th December 2018, 16:51   #14
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The actual fault is described as "CANBUS Messages Failure Instrument Pack 3" ..
I would like to know how exactly the CAN bus is involved in the operation of the HRW.

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Old 4th December 2018, 22:31   #15
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Thanks for all the answers guys.

I changed the battery to a Varta Silver Dynamic 74Ah 750A. The voltage it's 12.7 - 12.8 now, the alternator charging at 14.4 - 14.5. The car starts much better now.

After that, the gauges works intermittent - > VIDEO

The problem it's the NEC marked with blue in this PHOTO?

If this is, isn't easier to take out the NEC from my spare DDE4 and put it on my main one? Like this I can still have the car original ECU.

I've did that before on a navigation system (android aftermarket) and it worked.
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Old 4th December 2018, 23:34   #16
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Originally Posted by Alexandru.Edward View Post
Thanks for all the answers guys.

I changed the battery to a Varta Silver Dynamic 74Ah 750A. The voltage it's 12.7 - 12.8 now, the alternator charging at 14.4 - 14.5. The car starts much better now.

After that, the gauges works intermittent - > VIDEO

The problem it's the NEC marked with blue in this PHOTO?

If this is, isn't easier to take out the NEC from my spare DDE4 and put it on my main one? Like this I can still have the car original ECU.

I've did that before on a navigation system (android aftermarket) and it worked.
Change the 95P08 from the defective ECM into the working one, the little 8 pin SOIC in the middle of the PCB, it will be much less likely to end in tears

Brian
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Old 5th December 2018, 00:05   #17
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I would like to know how exactly the CAN bus is involved in the operation of the HRW.

Simon
That's for you to find out Simon, I'll give you a clue though it is something to do with multiplexing CANbus and K-Bus and DS2-Bus within the IPK and how the ECM interacts with the HEVAC ECU

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Old 5th December 2018, 09:15   #18
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That's for you to find out Simon, I'll give you a clue though it is something to do with multiplexing CANbus and K-Bus and DS2-Bus within the IPK and how the ECM interacts with the HEVAC ECU
In other words, you don't know either! For the benefit of other members, what you have done there is to list some factors associated with the instrument pack and HRW button irrespective of their relevance to my earlier comment.
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Well I can assure you Simon, that in this case you are completely and utterly wrong :
In fact you are "completely and utterly wrong" Brian because the DS2 (on board diagnostics) bus has nothing to do with the operation of the HRW and neither does the ECM, but then it sounds good quoting those doesn't it. You have also missed the BCU from your list which actually activates the HRW relay! Perhaps you didn't think that was important. Maybe you should have added the ICE system as well since that uses the rear window heating elements as an aerial.

Nothing you have said assists with my original statement that I would be surprised if the CAN bus has anything to do with the HRW operation, which I stand by.

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Old 5th December 2018, 13:27   #19
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I'm sorry Simon but you are incorrect.
Why then does replacing the EMS ECU correct the problems?
I have a pile of ECU's with this exact problem, it's failure of the Can-bus controller within the ECU, as Brian said above there's no particular reason. Some of the ones I have are prestine with no sign of water ingress they can and do sometimes give up the ghost.

The Can-bus does indeed have a direct link to the operation of the HEVAC and operation of the HRW

Russ
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Old 5th December 2018, 14:13   #20
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Thanks for your attempted explanation Russ but I'm afraid it's not clear.
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Originally Posted by BigRuss View Post
Why then does replacing the EMS ECU correct the problems?
The EMS? I think you mean the ECM don't you?
Quote:
The Can-bus does indeed have a direct link to the operation of the ... HRW
How?
The HRW relay is controlled by the BCU which has no CAN bus connection.

This is how the HRW works (on my KV6). The on-off button provides an earth to the BCU (C0662-5) which in turn energises the HRW relay (C0660-14). The elements supply is directly from the battery.
When the external temperature is below 10°c the BCU uses that data (C0660-18) provided by the IPK on the K bus (C0230-3) also to energise the HRW relay. The IPK converts the external temperature sensor analogue signal (C0233-4) into digital for transmission on the K bus.

Your mission Russ is to explain how the CAN bus allegedly fits into that straightforward scenario!

Simon
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Last edited by SD1too; 6th December 2018 at 09:04.. Reason: Additional explanation
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