Anthracite XM 2.0 SEi Turbo Manual

[Dieselman]

It looks like the speed sensor feeds into the amplifier box, then onto the Hydractive ECU on pins 6 and 13

[Aerodynamica]

That's really useful Jordan thanks - the trip computer is also faulty so you could be on to something!

[Aerodynamica]

Update:
I took out the speedo sensor amplifier box

And popped it open for inspection

There were no obvious signs of dry solders or burned out resistors or diodes etc

I inspected it with magnifyer for a long time.
I poped it into an oven at 230degrees for 2 minutes and opened the oven with the heat off. Nothing melted but hopefully was enough to reflow the solders. Refitted it and went for a spin. The suspension did its usual - fully working soft-hard switching for the first kilometer then sticks in hard. O well.

Checked the volts at the hydractive pin 13 white and pin 10 black plug to check the volts from both speed sensor and throttle sensor individually to find both seem to give voltage of 1.5 and 3 volts respectively. Not sure about the 3 volts but the 1.5 is seemingly right for the accelerator sensor according to the diagnostics check guide I have.

Returned to re read the fault codes only this time no faults showed up! Every other time after a run it is fault 24 - vehicle speed sensor but not this time. Still went to hard mode though.

Ignition back on after 10 mins and the electro valve clonks as usual and soft mode returns. This is what it always does - soft mode comes back after a wait.

I gavce up on the speed sensor though I still note that the MPG/ average MPH etc display still goes faulty -showing 7 mph and the like when you're doing 40. 99.9 mpg when you're ragging along up a hill so that too is not getting speed info properly.

I decided to disconnect the accelerator pedal sensor again. This does an odd thing - it actually stays in fully SOFT mode. No amount of ragging around country lanes makes it go to hard mode at any speed (so far as I've seen) It's as though disconecting this causes the ECU to ignore all inputs like the car is stationary.

I removed the full sensor

I then reconnected it so it can be moved by hand to cause the car to go to and from hard mode with it stationary. Whether it is connected or not it stays in soft mode all the time regardless of the speed. But! if I continually move this sensor lever whether stationary or not, it eventually goes into hard mode and stays there so it looks like the ECU doesn't like the signal from this red sensor at the accelerator pedal.

It could be that both the duff signal from the speed sensor and the pedal sensor together are causeing the ECU to go to fault (hard) mode until reset by switching off ignition for 10 mins or so.

SO!
I need a new speed sensor control box thing and a replacement red sensor for the accelerator pedal.

Anybody have them?

Next thing is the leaking steering pinion.

This is getting worse! Odd thing is I still cant pinpoint the leak.. It -looks- like the pipe unions towards the back of the pinion valve are oozing LHM out but at the LHM wetness seems to also appear above the pipes suggesting it's leaking out the shaft seal of the steering cardan shaft as it goes into the pinion valve. I just don't know! I've had several helpers moving the steering as I watch the thing from underneath and I just can't see it leaking! It just seems to build up with LHM around the pinion valve..
This is the view from the driver side wheel arch - these are the two suspect pipes but it could easily also be from under the white plastic cap above them.

Anyone know what size/ type of seals are used for these two pipes?

I need to try everything before embarking on the replacement pinion valve route!

[Aerodynamica]

So, pinion valve replaced and leak free, still getting LHM oozing out below the electro valve on the front subframe (though about 1/8 as much LHM as before!) so after all the effort and cost, the bloody thing still would fail an MOT test on LHM leak.

Thanks to Paul, I now have all the electric bits needed to try and fix the hyperactive suspension. The black box thingy was fitted in about one minute, nice and each of the two pedam movement sensors were connected but not mounted so I could test the workings of it manually. Not a good result I'm afaid.. both of the sensors work but as before, after about a minute of moving the lever on the sensor, the electro valve stops operating (i.e goes into and stays in hard mode) even if the car is stationary and running or even if it's not running but the ignition is on and a door open it still goes to sleep after a minute.

So either all of the red sensors are dodgy or there is another problem (no fault codes recorded)

Speed sensor - same result: travelling along the RH display shows incorrect speed if set to 'average speed'. MPG etc all wrong E.g 99.9 mpg regardless or just dashed lines.

Fitted the new speed sensor and made no difference.

I'm getting stumped now, all earths rebuilt, black box replaced, speed sensor and pedal sensors replaced, yellow light on dashboard lights up and goes out as normal, after a drive the fault code is always the same: 24, vehicle speed sensor.

Engine idle is still terrible until it's heated up.

I need help!!

[White Exec]

Bit worried about your oven treatment of that p.c.b. Assuming that 230degC was enough to re-melt the solder used on that board (melting point can vary enormously for different electrical soldering alloys, 90-450degC), it would probably be enough to damage some of the components themselves, which would never have been designed to operate at such a temperature. Soldering individual joints with an iron would not subject the components to such a high temperature, unless the joint was massively over-soldered.

Have never heard of this procedure before, and am quite sceptical about it.

Re: the accelerator pedal sensor, for the suspension to go into firm mode, the ECU is looking for a rapidly changing voltage output from the sensor (i.e. looking for hard acceleration). One way of fooling the ECU into thinking that hard acceleration is NOT taking place is to disconnect the pedal sensor output (pot wiper) cable, and connect a resistor from the cable leading the the ECU (black box in your case) down to earth. Value of the resistor should be what the pot provides in "pedal up" position. This fools the ECU into thinking that the pedal does not have a foot on it, and the suspension should stay soft however hard you press or waggle the pedal (unless some other sensor makes it go firm, of course). The same result should be achieved by what you have already done - removing the pedal pot, but leaving it connected, ASSUMING, THAT IS, THE POT IS ELECTRICALLY OK. Substituting a resistor at least eliminates the pedal pot as a culprit.

[Aerodynamica]

Have never heard of this procedure before, and am quite sceptical about it./QUOTE

It's crude true but it works for surface mount electronics so I thought it might work on this too. I restored my 2007 Macbook Pro having suffered GPU failure using the 'oven method'. It isn't advised really for this though but Paul sent a replacement black box anyway.

Re: the accelerator pedal sensor, for the suspension to go into firm mode, the ECU is looking for a rapidly changing voltage output from the sensor (i.e. looking for hard acceleration). One way of fooling the ECU into thinking that hard acceleration is NOT taking place is to disconnect the pedal sensor output (pot wiper) cable, and connect a resistor from the cable leading the the ECU (black box in your case) down to earth. Value of the resistor should be what the pot provides in "pedal up" position. This fools the ECU into thinking that the pedal does not have a foot on it, and the suspension should stay soft however hard you press or waggle the pedal (unless some other sensor makes it go firm, of course). The same result should be achieved by what you have already done - removing the pedal pot, but leaving it connected, ASSUMING, THAT IS, THE POT IS ELECTRICALLY OK. Substituting a resistor at least eliminates the pedal pot as a culprit./QUOTE

- Trouble is, I've already ran the car with the pedal sensor actually disconnected. The result is that it stays in soft mode constantly. But I think this happens because the ECU is also not getting a signal from the speed sensor (for whatever undetermined reason so far) so the ECU thinks the car is stopped or less than 30kmh. When it stays in perma-soft it also shows that it will not go into sport mode when selected (hyperactive 1 so sport = perma firm) but as far as I know sport mode should only activate above 30 kmh so again, it seems that the speed sensor is the issue.

I don't want the ECU to be tricked into thinking the pedal is not moved. I just want it to work as it should!

Do you know a test to check the condition of the pedal sensor? I now have three of them..

I really wonder that the

[White Exec]

Try this for sensor info and testing. Contains H1 and H2 info...
http://homepages.igrin.co.nz/simon/imag ... ive_II.pdf

[Aerodynamica]

Thanks for that, I'll have a look

[Aerodynamica]

That is a useful document but seems to be more for H2 as opposed to H1. It mentions pin 12 on the black plug for the pedal sensor but there is no pin 12 on H1. But it gives a good description of the sensors.

Odd thing happened:
I discovered there is still a serious fault with the Hydractive. A set of replacement pedal sensors all cause the thing to go to hard mode after a minute. After looking at the document Chris sent, it shows the resistance of the 'protection' resistor as 2.5kohm and the actual variable resistor as 4.7kohm. I measured these with a multimeter as 1.7 and 4.5 respectively. With the lever of the sensor at full 'up' position the resistance should be the value of the two resistors (I think?) but it only summed to about 5.8 on two of the sensors I have (including the car's original) one of Paul's supplied ones did however have higher resistances that seemed closer to the values in the pdf. so I thought I was on to something. I connected the third, good sensor and set about causing the hydractive solenoid switching. Unfortunately it did its usual - clicked away for a minute or so then went to sleep and went into hard mode (silence from the solenoid via LW radio) every time.

I decided to hook up the voltmeter to see what was being supplied to the sensor via the ECU and found it was 5v (the document says it should be 3.8v) although the 3.8 might be the V out with the potentiometer fully moved (throttle pedal down to the metal) - don't know the current so cant work it out. Anyway, to get to the odd bit. When the multimeter was connected to the plug at the pedal sensor with the ignition on, if I switched the multimeter from 100mV to 2V ranges it actually caused the hydractive electro valve to switch....

I was basically operating the hydractive via a multi meter dial.

Why is it funny? well in this state the hydractive kept operating for a full 5 minutes before it went to fault mode as usual - the use of the mulitmeter as a potentiometer instead of the car's own pedal sensor let it work for longer before it chucked it and went to hard mode. It makes me think the problem isn't with the senor(s) because whatever sensor is connected (one of the three pedal sensors or a multimeter) it still goes to fault ode. I wonder if the ECU has a fault?

As an aside, the speed sensor still doesn't work. I've got 3 sensors and just changed the black box amplifier and still that's the only fault rcorded on the hydrative ECU, and the MPG computer shows no proper speeds. What could cause this??

Since the Hyractive workings are all based on the vehicle speed as outlined by the technical guide in the pdf. then it probably isn't working at all right due to the lack of vehicle speed sensor. Trouble is the going into hard mode after a minute/ mile on the road can also be made to happen when it's stationary (via the pedal sensor) so wouldn't need the speed sensor anyway. Process of elimination says the fault is seperate from the speed sensor's input.

Surely this fault is cuased by the pedal sensor alone?

Anyway, I lose my storage this sunday so the XM has to be brought into service now to replace the CX so I've disconnected the pedal sensor that makes it stay in soft mode constantly ( probably due to the speed sensor not feeding in a signal too) that is probably too soft for constant use but at least it's not always hard!

The quest to fix this continues....

Anyone with a spare hydractive 1 ECU i can try - be in touch!!

[Dieselman]

Hydractive 1 is meant to stay in soft mode below 30kmh, so the speed sensor is necessary and might be the reason for the switching to hard mode, which is the default.