[no10ranger]

The interesting thing is that the diagram shows wire 7842 is spliced (E784). Your wiring data may show where that spice is. I am not sure how the spice is implemented but it could be an inline plug and socket so it would be worth looking for and checking.

Hi Ian

I think i have make a mistake as the wiring diagram was for a Car with ESP which mine doesn't have.

The splice in the wire would (E784) would be where is would have tire inflation detection that how I realized I had clicked on the wrong one at the start so i have reselected the car without ESP and below is the diagram which this one doesn't have the splice in the wire. It does have a double number thou 7842A/7842E not sure what this means.

Thanks Graeme

 

[Ian M Davis]

Thanks, I was wondering about that. You had posted ABS version on the wiring diagram before which was the diagram I had identified the 7842 wire from. I don't know why there are alternative numbers on the same wire.

 

[Ian M Davis]

Thanks, I was wondering about that. You had posted ABS version on the wiring diagram before which was the diagram I had identified the 7842 wire from. I don't know why there are alternative numbers on the same wire.

Hi Graeme,

When you get to look at the car again can you check one thing for me? My understanding of immobilisers is that they turn off both the ignition and fuel pump. Are you able to confirm the fuel pump is turned off? I think with your original fault the fuel was okay but you had a slow spark rate.

 

[no10ranger]

Hi Graeme,

When you get to look at the car again can you check one thing for me? My understanding of immobilisers is that they turn off both the ignition and fuel pump. Are you able to confirm the fuel pump is turned off? I think with your original fault the fuel was okay but you had a slow spark rate.

Hi Ian

I’m sure I can still here the fuel pump priming when ignition is on. But I’m sure I read that the immobiliser stops spark and the injectors from working I may be wrong.
How would you suggest is the best way to check the fuel pump.

Thanks Graeme

 

[Ian M Davis]

Hi Ian

I’m sure I can still here the fuel pump priming when ignition is on. But I’m sure I read that the immobiliser stops spark and the injectors from working I may be wrong.
How would you suggest is the best way to check the fuel pump.

Thanks Graeme

If you can hear it that's good enough. What I was really interested in - does the immobiliser cut off the fuel supply as well as the spark. I had assumed it turned the fuel pump off but stopping the injectors also makes sense.

With your original fault I understood petrol was reaching the cylinders. If the injectors are off now it confirms the current problem is different.

 

[no10ranger]

Yeah I would say fuel was getting to them as you could see and smell it on the plugs but this time when I was checking for the spark I took one of the plugs out and I wouldn’t say it was soaking and I would say you would expect it to be due to the amount of times I have tried turning over

 

[Ian M Davis]

Yeah I would say fuel was getting to them as you could see and smell it on the plugs but this time when I was checking for the spark I took one of the plugs out and I wouldn’t say it was soaking and I would say you would expect it to be due to the amount of times I have tried turning over

Thanks. When I think about it makes more sense to disable the injector than the pump.

 

[no10ranger]

Thanks. When I think about it makes more sense to disable the injector than the pump.

Hi Ian

Checked the wire going from 40v NR Pin10 on the Bsi to 53vNR Pin19 on the ECU and all rang out fine had a look at the pins on the bsi and all look ok aswell

thanks Graeme

 

[no10ranger]

One think I was thinking could there be dry solder joints in the bsi causing noise. When I opened it the last time all looked fine but solder joints looked to have a film over it as when I aired my heat gun at then they didn’t reflow the way I would expect

Thanks Graeme

 

[Ian M Davis]

One think I was thinking could there be dry solder joints in the bsi causing noise. When I opened it the last time all looked fine but solder joints looked to have a film over it as when I aired my heat gun at then they didn’t reflow the way I would expect

Thanks Graeme

It is starting to look like a fault in the BSI. I would expect the BSI and ECU to be talking over the CAN bus so it would worth re-checking the resistance of the CAN bus at the OBD connector to see if it's still 60 Ohms.

The lead free solder they use these days is not as good as the 60/40 solder. I would try wobbling the BSI connector that connects the CAN bus before trying to reflow the solder. The weakest point on the PCB is where the connector joined.

If you can't get anywhere it would be worth getting the part numbers off the BSI and ECU and see if you can find ECU kit (BSI, ECU and key). The kits usually include an ignition switch but all you need to do is swap the old key's blade to new key case. There may be some on eBay but this Dutch company seems to have good range: https://bartebben.com/online-parts-...uwjaar=2009&zoekwoord=Ecu&zoektype=4&groep=EC

 

[no10ranger]

It is starting to look like a fault in the BSI. I would expect the BSI and ECU to be talking over the CAN bus so it would worth re-checking the resistance of the CAN bus at the OBD connector to see if it's still 60 Ohms.

The lead free solder they use these days is not as good as the 60/40 solder. I would try wobbling the BSI connector that connects the CAN bus before trying to reflow the solder. The weakest point on the PCB is where the connector joined.

If you can't get anywhere it would be worth getting the part numbers off the BSI and ECU and see if you can find ECU kit (BSI, ECU and key). The kits usually include an ignition switch but all you need to do is swap the old key's blade to new key case. There may be some on eBay but this Dutch company seems to have good range: https://bartebben.com/online-parts-...uwjaar=2009&zoekwoord=Ecu&zoektype=4&groep=EC

If I have to go down the ECU BSI kit does that effect the mileage display on the car ?
Also would it just be a case of switching the BSI ECU and key over and all should be good ? I’ll check the CAN Bus tomorrow can you remind me of the pin nos I should be getting 60 ohms at

Thanks Graeme

 

[no10ranger]

If I have to go down the ECU BSI kit does that effect the mileage display on the car ?
Also would it just be a case of switching the BSI ECU and key over and all should be good ? I’ll check the CAN Bus tomorrow can you remind me of the pin nos I should be getting 60 ohms at

Thanks Graeme

There is also a Shunks fuse on the bsi that they say make the unit do a full reset if you pull it out and leave it 15 mins do you think this could be work that a try

 

[Ian M Davis]

There is also a Shunks fuse on the bsi that they say make the unit do a full reset if you pull it out and leave it 15 mins do you think this could be work that a try

The CAN bus is on pins 6 and 14 of the OBD connector (they are opposite each other).

Changing the ECU kit may reset the mileage of the car. The mileage is stored in the display and in the ECU/BSI. The car mileage will be reset to the higher of the two.

Provided you get exactly the same BSI and ECU as you already have it should work ok. The kit should include a new ignition switch and key but rather than change it I would move the old blade to the new key (or move the new key's PCB to your old key case. Unlike the older key types your key type doesn't have a seperate transponder chip. The transponder is within the main processor and is coupled by a small coil near where the transponder chip used to be).

By all means try the shunt fuse. I think it has two positions one being for redelivery transport.

 

[Ian M Davis]

Hi Graeme,

I was just had look on the Internet for similar problems and I found a bit more in formation about the key recognition the BSI goes through. It's two stages:
1. Identification
2. Authentication

Your diagnostics show both these stages have passed. The authentication is quite complicated and involves encryption and some calculations. This past on the first attempt. Hence, I think the BSI is receiving data okay from the ECU over the CAN bus but the ECU is not receiving receiving the unlock code from the BSI.

The problem could be with the CAN bus line driver in the BSI but there is one other device on the CAN bus and that is the ABS. The CAN bus links through the ABS. Hence, I suggest you find the ABS module and check its connector. It would also be worth finding the wiring diagram for the ABS and checking its power supply: 12V and ground.

 

[no10ranger]

Hi Graeme,

I was just had look on the Internet for similar problems and I found a bit more in formation about the key recognition the BSI goes through. It's two stages:
1. Identification
2. Authentication

Your diagnostics show both these stages have passed. The authentication is quite complicated and involves encryption and some calculations. This past on the first attempt. Hence, I think the BSI is receiving data okay from the ECU over the CAN bus but the ECU is not receiving receiving the unlock code from the BSI.

The problem could be with the CAN bus line driver in the BSI but there is one other device on the CAN bus and that is the ABS. The CAN bus links through the ABS. Hence, I suggest you find the ABS module and check its connector. It would also be worth finding the wiring diagram for the ABS and checking its power supply: 12V and ground.

Hi Ian

I knew the Can system ran through the ABS module. This is located behind the passengers front wheel.
I had in my head that if there was a resistance level if 60 ohms this would then mean it’s ok.
I’ll take the wheel off and have a look at it and check what you suggest.
By looking at the diagram it’s the only other think that links the BSI and the ECU. When you say there is a bit involve in the encryption and the ECU is getting information to the BSI do you not find it strange the ECU isn’t unlocking as they must be doing a bit of back and forth with information to complete the encryption would they not ?
Thanks Graeme

 

[Ian M Davis]

Hi Ian

I knew the Can system ran through the ABS module. This is located behind the passengers front wheel.
I had in my head that if there was a resistance level if 60 ohms this would then mean it’s ok.
I’ll take the wheel off and have a look at it and check what you suggest.
By looking at the diagram it’s the only other think that links the BSI and the ECU. When you say there is a bit involve in the encryption and the ECU is getting information to the BSI do you not find it strange the ECU isn’t unlocking as they must be doing a bit of back and forth with information to complete the encryption would they not ?
Thanks Graeme

I think the description at the end of this discussion is about right: C5 BSI, Transponder, Coding Issues - French Car Forum . It is suggesting that the BSI does almost everything. Certainly if you look at the BSI logs you got from Diagbox it lists
Identification and Authentication as being complete in the BSI section. However, going by the log for the ECU I suspect it may generate the initial encryption seed (i.e. the random number) and then transmit it to the BSI and then waits for the BSI to send back response.

The CAN bus line driver has a transmitter and receiver in the one chip. Normally you would expect both to fail unless there was a dry joint on one of the pins e.g. the transit pin of the chip.

The interesting thing about the CAN bus is that only the two computers BSI and ECU have a120 Ohm termination. Other items on the bus don't change the bus resistance. However, if the connection was poor at the ABS you may measure a higher resistance (>60 Ohms) at the the OBD connector. The other thing I had in mind was your comment about noise on the bus.

 

[no10ranger]

I think the description at the end of this discussion is about right: C5 BSI, Transponder, Coding Issues - French Car Forum . It is suggesting that the BSI does almost everything. Certainly if you look at the BSI logs you got from Diagbox it lists
Identification and Authentication as being complete in the BSI section. However, going by the log for the ECU I suspect it may generate the initial encryption seed (i.e. the random number) and then transmit it to the BSI and then waits for the BSI to send back response.

The CAN bus line driver has a transmitter and receiver in the one chip. Normally you would expect both to fail unless there was a dry joint on one of the pins e.g. the transit pin of the chip.

The interesting thing about the CAN bus is that only the two computers BSI and ECU have a120 Ohm termination. Other items on the bus don't change the bus resistance. However, if the connection was poor at the ABS you may measure a higher resistance (>60 Ohms) at the the OBD connector. The other thing I had in mind was your comment about noise on the bus.

Hi Ian
Had a read at the post and yeah most happens at the BSI and it seems to be the last stage is the bit that isn’t happening.

I will have a look at the the wiring of the Abs unit and put a post up for your reference and will get a look at it today.

Regarding noise in the Can bus network the only way I think I would know for sure would be to check with a oscilloscope which I don’t have.

Thanks Graeme

 

[Ian M Davis]

Hi Ian
Had a read at the post and yeah most happens at the BSI and it seems to be the last stage is the bit that isn’t happening.

I will have a look at the the wiring of the Abs unit and put a post up for your reference and will get a look at it today.

Regarding noise in the Can bus network the only way I think I would know for sure would be to check with a oscilloscope which I don’t have.

Thanks Graeme

In the case of noise I think you only need to make sure the connectors are okay.

 

[no10ranger]

In the case of noise I think you only need to make sure the connectors are okay.

I was thinking more if a dry solder joint was causing it

 

[Ian M Davis]

I was thinking more if a dry solder joint was causing it

yes that's possibility. Contact resistance is a common cause or some moisture tracking across terminals