Anthracite XM 2.0 SEi Turbo Manual

[Aerodynamica]

That's a good solution - might do similar

[Aerodynamica]

Anyone know how to reach the steering sensor?

[xantia_v6]

It occurs to me that the behaviour of the ECU going into safety mode after a few minutes might be because it is not seeing any dynamic info from a sensor while driving. If this is the case, then disconnecting the faulty sensor might not change the symptoms.

[JD01JD]

Before going any further with the Hydractive fault finding I would take a look at this file: download/file.php?id=396

The "blinker" circuit described in the file is easy and cheap to make but is extremely useful if you don't have a Lexia — you can check and clear error codes in ALL the ECUs, not just the Hydractive.

What I would do is build the blinker circuit and clear the fault codes on the Hydractive ECU. The Hydractive light should illuminate for a few seconds when the ignition is turned on if all faults are cleared. Once they are cleared take it for a drive, then read the codes again. Now only current faults will be recorded and should hopefully tell you whats wrong.

When I got my XM the suspension was acting exactly the same, soft for 500m or so then hard for the rest of the drive. I suspected the speed sensor as the fuel computer also wasn't working (although I think average speed didn't work also, unlike yours) and the code reader confirmed it.

Jordan.

[captainhaddock]

This is only possible on series one according to what I understand?

[Aerodynamica]

Thanks folks, some really good ideas here - You're right, if one sensor was not sending a signal anyway then discionnectine one or more wouldn't show this - I hadn't thought of that.

The ECU is the 'H3' type and I am not certain if that's the type that still runs with a sensor disconnected. I'll have a look at the file of the LED tester as it sounds pretty interesting.

I'm beginning to really enjoy the first half mile of any journey!

[Aerodynamica]

I've had a look at the fault code and reader excel files and probably learned more in 10 minutes than in several weeks of mini tweaks to the car!

The little circuit is simple enough but I was unsure of how the LED flashing equates to a particular error code - anyone made this device to check ECUs?

[JD01JD]

I have used it to read the ECUs before. After closing then opening the switch it will start to blink the code. It will blink the first number, pause, and blink the second number. For example blink blink pause blink blink blink would be 23, it's easy one you get the hang of it. I still use mine although I have a lexia, it's much quicker if you just want to read and clear the codes.

Also the file gives instructions on S2 use although I don't know if it works? You just have to use certain pins in the 30 pin connector, otherwise it's the same as S1. I think I read somewhere that the S2 30 pin connector just terminates the single wire connectors of the S1 into the plug an the lexia chooses what wire to use, if correct it will defiantly work.

Jordan.

[xmexclusive]

I can confirm that Jordan is right in all his descriptions above.
The Lexia contains a series of relays to switch between socket pins to read the required data lines.
It has a computer programme to read the same pulses that the little LED circuit displays.
The Lexia then uses its look up table to display identified fault information.

Using that little LED circuit for individual ECU's can make the fault checking and clearing processes much easier to understand.

Lexia programmes can be a real pain to set up and get working.
With Mk2 cars the 30 pin socket and leads can cause real wire continuity problems in getting reliable Lexia reading.
Many of the Chinese 30 pin lead plugs need modifying to fit the car sockets properly.
Only the 30 pin to round plug type leads have the correct wiring to suit XM's and most types of Lexia.

When the Lexia fails me I use the LED circuit to check if the problem is with the car or the Lexia and its wiring.

I will see if we can start a separate post listing ECU fault codes.

John

[Aerodynamica]

Thanks chaps, it'll take a little bit of time to get the 12v LEDs and resistor etc and in the mean time I reconnected the body motion sensor and again, same behaviour - goes into hard after a mile, nothing new.

A problem I noticed on the drive home after collecting the car a few weeks ago was that the steering column was not straight - the reach/height adjustment was really stiff and seemed asymmetrical. I wanted to have a look at the steering angle sensor and the throttle sensor anyway before I have the LED tester available so removed the column surround to find some strangeness. Firstly, right away I found the mounting nuts of the column were totally off centre so that was a nice simple explanation to the off centre steering wheel- loosened, centred, retightened and boom! fixed. I noticed that after taking out the steering wheel control commutator ring that the steering sensor was behind it but odd thing was that the optical disk was not actually running between the sensors


I removed the sensor and connected it to the plug and with the igintion on was expecting to see light appear in the little slots on one side but nothing (doesn't mean anything as I don't know for sure if it is visible) Anyway, cleaned the whole thing with contact cleaner as it was very dusty and refitted it with the optical disk running in the slot of the sensor as I assume it does. I first assembles things with the steering sensor disconnected and went for a drive - usual result: stays soft for a mile then hard. Back, reconnect the steering sensor and refit the column surrounds and next disconnect the plug at the accelerator pedal, I'm expecting this to make no difference like the rest because the fault is still to be read by the LED reader.

Odd result. It stays in soft mode now - permanently. Using LW radio you can now hear the electrovalve doesn't disconnect at all regardless of speed, steering hump-backed bridge or other. Switch to sport mode and...... still soft.

I wasn't expecting that at all and I must say that although it's clearly still not working properly, I can live with the perma- soft mode better than the sport until it's diagnosed.

Is this to be expected?

Also, the steering feel has improved a good bit after straightening the column - it must also have been rubbing on something.

The HP pump has quietened down a couple of days after replacing the pump suction hose clips so perhaps the pump was half full of air.

The new throttle position sensor arrived today too - very quick dispatch indeed. In the day since i ordered it I disconnected the current sensor and cleaned the connections and refitted. Today the throttle response was bang-on with no hint of revs dropping. Damn intermittent faults - I'll keep the new TPS in the glove box for now.