A Possible Little Earner?, Electronic component repairs

[Robin]

Sadly our cars are getting to the stage where little gremlins and failures are becoming a 'known' such as the diode failures on hydractive valves and the consequential ECU failure, the dashboard screen giving information and occasionally the lamp failures in the radio display.

I daresay there are a few others too but I have not, as yet had anything else.

So is there an electronics whizz out there willing to take on the repairs of these components for a fee?

They are all small enough to be posted out.
Robin.

[noz]

Hi Robin,

Your post was looking a bit lonely there. I don't have formal electronics background but I hae some self-taught capability. Certainly replacing the VN05N's in the ecu that burn out due to the failure of the said diode is well within my capability. I have done my own just recently adding new diodes to the pcb of the ecu rather than at the electrovalve end. I also used larger diodes which should be less prone to failure.

I have however failed to find a solution to the missing pixels on the LH display. The failure is completely down to the ribbon cable joining the pcb to the LCD screen. I can't believe that the world of Xm ownership is stumped for a ribbon cable. Someone, somewhere must have a solution to this.

In answer to your original question, I would volunteer my (limited) services for some fixes. I'll start the list off here if anyone else wants to add to it:

• 1 Repairing the suspension ecu's by the replacement of the VN05N's and addition of new diodes.
  
• 2 Repairing of the fan heater modules for speed control of the fan.

Cheers

noz

[Robin]

Cheers Noz.
I do not have any electronics knowledge at all - I was brought up in the days when we had solid state and mechanical switching - at least you could see what was happening or not as the case may be. Additionally my eyesight is now such that I can barely see many electronic components let alone repair them!

I have the solenoid valves to check and or replace on my XM but I suspect the ECU will need attention.

Can you tell me, is the car still safe to drive with the ECU disconnected? If not and we know the solenoids to be good would a swap of ECU's be a practical proposition?

We could do surcharges, payments etc. via PayPal.

You can probably tell by now that I am leading up to giving you the job of going over my ECU this year

Robin.

[Peter.N.]

Hi Robin

You can use the car without the suspension ECU but it will be permanently in hard mode.

I am a retired TV engineer but the electronics used in modern cars is beyond me without copious data. My eyesight is not to bad but I still cant see let alone solder some of these chips with about 100 pins. I grew up with valves and still understand them better!

Noz's grasp on modern electronics is very good and I would have no hesitation in reccomending him.

Peter.N.

[Ciaran]

Speaking of the ECUs and the diodes failing, I suspect mine may be getting to that stage. Front spheres look pretty new, and normally it behaves quite softly. The rear occasionly feels very hard though. I drove my parents Rover 400 yesterday as I was in a hurry and the XM was boxed in. Anyway, the River felt softer in the rear over speed bumps than my XM did, so certainly something very wrong!

Does anyone remember details of that mod that you could do to the ECU to make the dash light come on when the ECU was in / out of hard mode?
Perhaps Noz could do this when fixing the diodes, for an extra charge... some people might find it handy...
Not to give anyone extra work or anything mind you!

For the record, I'm not averse to soldering things etc, and have good eyesight for it, but my experience of electronics is limited, and nowhere near the standard of you guys I suspect. I did grow up taking things apart, however I'm more of an IT man these days....

[Robin]

OK Noz, over to you. Looks like it's time to put a few estimates together and let us know what you will require by way of used fivers

Robin

[archman1]

Noz
How on earth did you open your Hydraulic ECU. I've taken the screws out and tried to prise it apart with a screwdriver, no luck at all. Short of hitting it with a chisel I'm out if ideas.
Cheers
Steve

[noz]

Hi Steve,

Don't forget that the ecu lives in a fairly hostile environment so it has to be protected. There's a silicone gasket which lives just under the rim of the lid. The lid is the bit with the heat dissipation fins on and held in place by 4 torx screws. Take the 4 torx screws out and prise the lid off with a knife.

The components are on the underside of the pcb which are not accessible unless you remove the pcb from the housing. Remove the 4 brass screws from the edge where the connectors are and the 4 torx screws internally holding the pcb in place. Warm the seals at the connectors with a hairdryer. Lift the far end of the pcb gently to put some stress on the seals and gently prise the seals with a sharp knife. They come off no problem using this method. With the pcb in your hands the components are easily accessible.

Cheers

noz