1995 2.1td SX Auto Project

[josh2109]

Hi folks,

A bit of a delayed post after my initial introduction, as the project was put to one side. However, I'm back on the case with my XM and I'll do my best to document progress here along with probably a never ending list of questions as I get my head around some parts of the car.

Here she was as she came in:



The first thing I replaced was the accumulator sphere as it didn't appear to be working



This has improved the brakes and the suspension doesn't rapidly sink with the engine off now, so that's something ticked off the list.

I've looked into the slow starting, and I'm fairly certain air is getting into the system somehow. I have a Bosch pump:



The fuel heater is already looped out, so that's that crossed off. I've replaced the spill off pipes as one was leaking, but that hasn't cured the starting problem so there must be air getting in elsewhere. I've checked the glow plugs and they're all measuring sensible resistance and the relay works correctly. If you prime the fuel system via the button on the filter then the car starts fairly easily. The previous owner seemed to think that there was a leak in the fuel pump, and supplied me with a spare engine and pump to swap over - I'm not sure how I would diagnose this bar seeing a fuel leak on the fuel pump body?

Alongside this the wipers weren't working properly, and some investigation led me to find the passenger side spindle was seized. I've stripped that, cleaned and re-greased the parts, then rebuilt it.









I made an effort to ensure that things were lined up as they were before they came off, although it turns out where they were originally parking was quite far off.



I adjusted them to account for their travel, and all seemed good... until I refitted the painted scuttle trim. The drivers arm clatters into the trim when it parks. If I adjust it one spline up, it sails off the side of the windscreen at full travel. I'm sure it's parked in the correct position, but something isn't lining up properly anymore.



I'm pretty sure I've got the right arm on each side (my paint mark wore off before refitting...)




I feel like if the whole wiper assembly could rotate back on its axis somehow then it would be ok, I only need a few extra mm of clearance - there's absolutely no movement in the wiper assembly though when you slack off the fasteners.

So I need to have a think and come back to that.

Another problem I've only just started to investigate is the ABS. I appear to have a Bendix unit, and when starting the car the ABS light comes on, briefly goes out and comes back on again - it then stays on. From a little bit of bedtime reading I understand that this potentially means that the ABS self diagnostic starts but is failing at the first test. I haven't been able to find a list of blink codes though so I'm unsure what this is telling me. Presumably that an unobtainable sensor needs replacing...

The headlights have come back to life at least, and after replacing a sidelight bulb I now have a full compliment of lights.

I'm keen to get to the bottom of the wiper alignment and the ABS fault(s) as quickly as possible as once these are sorted I will put it in for an MOT. The slow starting is less urgent, but I will need to get to the bottom of that too.

Oh, and for some reason the boot has suddenly decided that it won't open - I can't tell if it has suddenly locked itself (it never used to lock on the central locking) or if the pull handle has stopped operating the latch. Does anyone have any pointers for releasing the hatch from the inside?

If I can get on top of the mechanical bits may even give it a wash soon, as I reckon that the green will look fantastic with the years of barn dust removed

[Dieselman]

The Emerald paintwork will indeed look fantastic once cleaned and polished, it is one of the best colours for an Xm.

I suspect you have the wiper arms reversed, but check the scuttle trim is high enough, if not the washers will spray into the trim.
The motor park position can't make the sweep different, just whether the wipers park at the lowest position, or not.
I take it the spindles are back in their correct positions?
A further thought is that the arms have been in the incorrect positions, if so ignore the splines and position the arms correctly, tighten the nuts which will create fresh splines in the aluminium arms.

For the Abs, it may be a sensor issue, or the power relay. A single blink and lamp back on indicates power relay issue, two blinks and then back on means a sensor fault.
The full list of fault codes are in the linked to thread, viewtopic.php?f=8&t=7368

For slow starting it probably is an air leak into the fuel pipe, to test either add a clear pipe leading to the pump and watch for air bubbles, alternatively try running the pump directly from a can of diesel, thus eliminating all pipework and filter.
If the pickup in the tank is blocked with gunge, or sitting tight to the base of the tank, the fuel pipe will be under greater suction, so more likely to suck in air.

You appear to be cracking on nicely and that looks a very worthy Xm to be restoring, keep up the good work.

[josh2109]

Thanks Dieselman.

You may be on to something with the idea of making new splines in the arm, I’ll try and remove the old ones as currently the arms slots into them as they’re so pronounced. If I can get just 5mm or so of clearance then it’ll be sorted. A friend with an identical car is checking which way round the arms should be.

It looks like it’s possibly the power relay then from what you describe. I have one of the pumps with an integrated relay so that will be fun… I also noticed that I don’t have any diagnostic ports in my ECU enclosure in the engine bay?

I like the idea of running the pump from a can of diesel to isolate the upstream components and just focus on the pump. I have some spare fuel hose with a priming bulb in from a diesel BX so I’ll have a bash at that in the next few days.

Now that I’ve got some momentum on this project I’m really looking forward to getting to a point where I can drive it.

[Dieselman]

I will try to check which way the wiper arms go. Looking at your images again I now think they are correct, the longer S shaped crank should go on the drivers side.

Being Series 2 Xm, you have a single 30 pin diagnostic socket under the steering column. Diagnostic socket connections. Note direction of socket as it reverses for Lhd/Rhd. The pins stay the same in the socket housing, so are also reversed.
You can either use a proprietary 30 pin connector, or just clip onto the relevant output pin and use a Blink Code Reader.

Post with socket layout.
viewtopic.php?f=8&t=6858&p=78746&hilit= ... ket#p78746

The Abs relay is just screwed onto the side of the Abs block, but inside the housing is only a circuit board with a relay and diode mounted to it. If the fault code indicates it is the relay that is faulty, cut it open and inspect for cracked solder joints, broken off diode, duff relay.
Glue it back together once repaired.

Regarding the boot lock being stuck, what has probably happened is the central locking servo has jammed in the locked position. The only way to open the boot is by holding the key hard in the unlock position and repeatedly operating the release handle.
Sort the servo once open, as the force of the boot lock being turned against the servo can break the plastic intermediate link.
A good clout will normally free off the servo mechanism, then apply some silicone grease to keep it free.

[josh2109]

Ah that's my mistake, I thought the 30 pin connector would be in the ECU box for some reason. I'll flash the codes out tonight and see what I've got. Would it be beneficial to put a momentary switch on my jumper wire? When I had a brief skim through it looked like clearing the codes required some specifically timed earthing of pins.

My ABS pump looks like this:




Do those allen screws come out to release the black cover? If so then should the code point me to the relay I may be able to do the work in situ. I saw some mention in other threads of cutting into the case, I'm not sure I'd be happy doing that without removing the unit first though.

Frustratingly the key lock on my boot is jammed, the key only inserts halfway. I'll try to free the keyway up with some silicone spray this eve, if not I'll just have to try cycling the central locking whilst rocking the boot lid (it doesn't feel fully latched) and praying. It's a minor problem in the grander scheme of things at present though.

[josh2109]

Just a quick update for my own reference as much as anything else - I ran the codes from the ABS module using a power probe. Initially it spat out nearly every code, but after recording them and clearing them it comes back with just two codes; 31 and 32.

I’ll try and track down the pins on the ECU connector to read the resistances next.

[Dieselman]

Never thought of using a power probe to extract codes...presumably it flashes an indicator on the actual power probe.

The relay box does indeed unscrew from the side of the Abs valve block, however codes 31 and 32 indicate wheel sensor faults:
31 = Rh rear wheel, Ecu pins 17 and 34
32 = Lh front wheel, Ecu pins 18 and 35

The relevant Abs error information, resistances and pin-outs are given in the error code information from the Blink Code reader thread, however for wiring diagrams please see Gabor's diagrams in the linked post. viewtopic.php?f=13&t=7592&start=110#p124757

As a result of your post I have just checked the error codes listing and found the listings are incorrect, with the Bendix and Teves listings being interposed.
Gabor's diagrams are correct, as we had a similar discussion when he first produced those as He had those reversed, possibly as a result of following information from the error codes list.
Use the Teves listing for the Bendix Abs system. I will update and reload the information.

[josh2109]

The power probe seemed like a good idea as I couldn't find any of the boxes of crimp terminals to make my own code reader, and it was basically what I needed (a small, precise contact with a momentary switch to earth) without having to do any assembly. I didn't even consider the light on it, but as you rightly say the ECU flashed the code out on the power probe's earth/green LED which was really helpful.

Thanks for clarifying RE the pins - I did find that confusing as doing my own testing I found the following:



The pair of pins circled in blue and the pair of pins circled in green give a reading of 2600 ohms.

The pair of pins circled in orange and the pair of pins circled in red give a reading that suggests open circuit - it's reading infinite on all the ranges.

Next up I'll track down the plugs for the sensors and check continuity at each part of the circuit.

I'm vaguely hoping that it's something repairable rather than sensors needing replacement as they don't appear to be easily obtainable.

Whilst I was in the ECU compartment I took out the Hydractive ECU also, and I noticed something rattling around inside which was not encouraging.

I took it into the garage and opened it up on the bench.




This was what was rattling around:



You can see that it's legs are still sat on the board:



So I'll need to order another MR751 diode and replace the damaged one.

I also noticed what possibly looks like dry solder joints:



So that'll require further investigation also.

It feels a bit like one step forwards two steps back at present, but I guess at least I'm finding and quantifying faults then coming up with plans to rectify them.

[Dieselman]

Your resistance tests appear to confirm the issue.
Rear sensors: 96067694
Front Sensors: 96161385
If you can't obtain those which have green connectors, just fit later blue connector ones;
Rear: 4545 53
Front: 4545 52

If you are lucky it's just a connector, or lead issue. The front connectors are clipped into the wheelhouse, the rears are on top of the rear subframe.
To check wiring continuity link each pair of connectors together with a piece of wire, then go to the sensor connector and test round trip continuity there.

Strange fault with the diode dropping off the board, but it looks like there may have been water entering the enclosure, so the contact points corroded.
The iffy solder joints look to have been over-soldered already.
You are bound to have some faults to fix, but won't have any issues given how you are getting on so far.

[josh2109]

Thanks for the part numbers, they’re a bit of a lifesaver! Long story short, I’ve tested the sensors again. The front one is completely dead, the rear one was out by 2000ohms and after cleaning the connectors it was out by 1000ohms at 3600. As luck would have it, both sensors that I needed were on eBay, last one in stock on both! I’ve got them ordered for £60 all in which I was happy with.

I’ve revisited the wiper, and even finely adjusted the best I can get it is that it slightly clips both the scuttle and the edge of the windscreen. I think there must be a small amount of play in the spindles and linkage from wear - I can work around this by obtaining a second passenger side wiper and fitting it on the driver’s side as the sweep is spot on if I do this.

On a tangent, I think I’m missing some dash lights:



I feel like there should be a warning lamp for the suspension, and an oil level gauge? Also, is that an LCD screen between the fuel and temp gauges? I don’t have an owner’s manual so haven’t got anything to check against currently.