2002 X5 3.0D - DiS errors - what it have to do?

[plouat]

Hello! I have 2002 X5 3.0 diesel and sometimes the car does not increase rpm and does not accelerate.
In DIS i receive the following errors:
1. 3505 DDE: Glow plug or glow plug system (Glow plug system - glow plug or glow-plug relay)
2. 1260 DDE: Pre-supply pressure monitoring (Rate reduction due to low pre-supply pressure)
3. 1470 DDE: Charge air pressure control (-ve control deviation/charge-air press. too high)
4. 05 MRS: Side airbag, front left (Resistance too low)
5. 02 LRA: Sensor fault, front

What can i do for each error to solve it and get over it.

Thank you in advance!

[Laurence]

1. 3505 DDE: Glow plug or glow plug system (Glow plug system - glow plug or glow-plug relay)

This would affect the cars ability to start as the glow plugs only operate when cranking the engine. Assuming the car starts OK, this would not be your problem - although it does need looking at. Possibly just a faulty glow plug.

2. 1260 DDE: Pre-supply pressure monitoring (Rate reduction due to low pre-supply pressure)

The diesel engine has two fuel pumps. The first is a lifter pump that moves fuel from the tank to the engine bay, this is low pressure pump. This then feeds the second pump which is a high pressure common rail pump. This delivers fuel to the injectors (around 30,000 PSI).
Its not clear from the faut code description what the pre-supply pressure is, whether its the lifter pump pressure or the common rail pressure.
I had similar fault with my car where the rail pressure was reported as low - it turned out to be the common rail pressure sensor (this senses the pressure supplied by the high pressure pump).
If the ECU thinks there is a proble with the fuel supply it can reduce power to the engine or shut it down - I've seen both.
I would start by checking the lifter pump and also the common rail pressure sensor, it is a lot cheaper to swap those out than the high pressure pump!!

Another thing worth checking is the leakback rate of the injectors. If the leakback is too high, this can cause the (high) pressure in the common rail to fall below the required amount.

3. 1470 DDE: Charge air pressure control (-ve control deviation/charge-air press. too high)

I have seen this once before when I had an injector fail. The ECU tries to compensate for low power output of the engine. i.e. you have your foot to the floor but the engine revs dont rise. I'm not sure why this happens, but it appears that the turbo will overboost to compensate for the lack of power, this then causes an error code. If you fix problem 2, this one should go away.

4. 05 MRS: Side airbag, front left (Resistance too low)
5. 02 LRA: Sensor fault, front

As for these two, I don't think these are related to your engine problem - The DDE code is the engine control module. I assume that MRS is airbag control and LRA could be parking sesnsors??

[plouat]

Originally Posted by Laurence

1. 3505 DDE: Glow plug or glow plug system (Glow plug system - glow plug or glow-plug relay)

This would affect the cars ability to start as the glow plugs only operate when cranking the engine. Assuming the car starts OK, this would not be your problem - although it does need looking at. Possibly just a faulty glow plug.

2. 1260 DDE: Pre-supply pressure monitoring (Rate reduction due to low pre-supply pressure)

The diesel engine has two fuel pumps. The first is a lifter pump that moves fuel from the tank to the engine bay, this is low pressure pump. This then feeds the second pump which is a high pressure common rail pump. This delivers fuel to the injectors (around 30,000 PSI).
Its not clear from the faut code description what the pre-supply pressure is, whether its the lifter pump pressure or the common rail pressure.
I had similar fault with my car where the rail pressure was reported as low - it turned out to be the common rail pressure sensor (this senses the pressure supplied by the high pressure pump).
If the ECU thinks there is a proble with the fuel supply it can reduce power to the engine or shut it down - I've seen both.
I would start by checking the lifter pump and also the common rail pressure sensor, it is a lot cheaper to swap those out than the high pressure pump!!

Another thing worth checking is the leakback rate of the injectors. If the leakback is too high, this can cause the (high) pressure in the common rail to fall below the required amount.

In the past i had two errors, but now is not present:

1470 DDE: Charge air-pressure control (-ve control deviation/charge-air press too high)
1613 DDE: Smooth running controller ( correction variable too large)
I don't know if are related...

[Rahu]

Seems that your broblem might be injector or injectors, you have to check correction of injectors. It should be inside to -5...+4

[Gregory891]

Did you ever sort out your faults / error codes? What resolved each of them (or all)?

[Gregory891]

I also had the 3505 fault code for at least a year. Car started well enough (DDE light system works, stays lit longer in colder weather - which is a sign that the control unit is working fine) but as my car has above 200.000 km, this then indicates glow plugs.

Glow plugs are reasonably priced (set of six Bosch with postage to my home for less than $100 US), you need to remove the intake manifold to replace them - so replace all six.

I recently had my glow plugs changed by my local mechanic (I didn't have time to do myself). Problem solved and I'm sure she'll start even easier in winter.