C5 X7 3.0 Hdi Suspension not raising

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IGriffen
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C5 X7 3.0 Hdi Suspension not raising

Post by IGriffen »

Hi everyone.
So I think I may have broken my Suspension. Did a service yesterday, raised the car to its highest and jacked up the front right but it slipped off the jack and crashed down hard but no harm was done. Finished the service then later I lowered the car to help load some heavy items and now it won't raise back up as the pump isn't working. It's got fluid and I've checked the maxi fuse. I've also checked fault codes and this is what I found:
U1118 Fault. Absence of communication with BSI
U1116 Suspension ECU data not valid fault
U2005 Triggering (Vehicle speed receipt anomaly)
I cleared them and only U2005 came back but think that's due to diagbox.
Car starts and there's no faults on the dash. Also the Suspension buttons bring up the raising or lowering display on the dash like normal.
Any help with this would be much appreciated as I know very little about how these cars work especially the electrical side.
Thanks in advance
Ian
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GiveMeABreak
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by GiveMeABreak »

U2005 can be ignored - it's returned as a result of querying the suspension ECU when and the car isn't moving.

U1116: is Suspension ECU data not valid fault: Protocol controller not functional
U1118: is Fault absence of communication with the built-in systems interface: No signal

So whatever has happened, that clunk has possible dislodged some connections at the suspension ECUs (you have 2 on the V6 - one on the BHI itself and the other is a separate one) or one of them has been damaged no signal is getting through to the BSI from the suspension ECU (s).
IGriffen
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by IGriffen »

That's brilliant thank you. I'm sorry your going have to dumb it down for me though. What's BHI stand for? Also any idea where I might find the other suspension ECUs?
IGriffen
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by IGriffen »

Thinking about the bonnet dropped when it feel off the jack and I had tools on top of the fuse/ECU box.
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GiveMeABreak
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by GiveMeABreak »

The second suspension ECU is in the rear of the car - so I would rule that out for the moment - the other ECU is on top of the BHI which is the assembly on top of the pump, with the ECU uppermost integrated on to the unit.

I think you've probably answered your own question regarding the thump and having the tools on top of the engine fusebox.

There are CAN multiplexed wires going from the Engine ECU to the BSI and similar to the suspension ECUs / Dash etc.


Have a look at the 24 pin Grey connector on the engine fusebox - Pins 11 (CAN High Speed) and 12 (CAN Low Speed) are the CAN wires to the BSI in the glovebox. Make sure they are secure and undamaged.
MGmike
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by MGmike »

There should be a fuse in the passenger compartment fuse box. Check your handbook to find the right one.
While the maxi fuse provides the main power to the pump motor the other fuse supplies the BHI, without that you get no power to the pump.
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kitchD6C
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by kitchD6C »

Hi Ian, Rich from Southways here. Sorry I couldn't help any more on the phone the other day, but as I suspected, these guys have got some ideas already.

Did BL Autos have any ideas? Or would they need to see it?
IGriffen
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by IGriffen »

Hi rich. That's ok thank you for your help. I haven't had time to sort anything out yet. I'm off work tomorrow so will ring them then. I'd like to try find a good Citroen specialist a bit closer than BL Auto's. Maybe someone on here knows anywhere around Hampshire that could help.
civvie
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Re: C5 X7 3.0 Hdi Suspension not raising

Post by civvie »

Is there not a Citroen specialist near where Top Gear is filmed. Or has age played tricks on me, someone should know if I'm talking rubbish