'92 XM V6 24 Immobilized in Germany

[wld]

In most cases the wiring problem lies between keypad and ECU, but there are exceptions.
The method works on my 1995 MK2 TCT, and a Xantia from 1996, with the same engine.
On newer models a trip to a tuner may be required for a "immo off" procedure.

[Eddie nuff]

Still wanting $5450 for it?

viewtopic.php?f=11&t=8334&hilit=xm+Germany" onclick="window.open(this.href);return false;

[Steinkul]

Hello, apply to
http://www.andre-citroen-club.de" onclick="window.open(this.href);return false;
They do understand English.

[JK99]

I experienced a similar problem with the immobiliser code early this year. Both the green and the red lights were on. It turned out that fuse F1, under the bonnet, had blown. When a new fuse was inserted, the immobiliser worked.

But when I started the engine, the fuse blew again, and immobiliser stopped working. Both red and green lights showed again.

The problem turned out to be a seized (frozen) EGR solenoid. Once this was removed, cleaned out , unfrozen and refitted, the car worked fine. However, it was not cheap to fix.

[JK99]

Just in case you are wondering, EGR stands for Exhaust Gas Recirculation.

[White Exec]

I experienced a similar problem with the immobiliser code early this year. Both the green and the red lights were on. It turned out that fuse F1, under the bonnet, had blown. When a new fuse was inserted, the immobiliser worked.
But when I started the engine, the fuse blew again, and immobiliser stopped working. Both red and green lights showed again.
The problem turned out to be a seized (frozen) EGR solenoid. Once this was removed, cleaned out , unfrozen and refitted, the car worked fine. However, it was not cheap to fix.

There have been a good number of reports of Red+Green on the keypad over recent months - keypad/ECU error. JK's remarks about F1 (engine bay) got me wondering, and his reported link to the EGR circuit, so I pored over a good number of circuit diagrams last night.

Manuals list engine bay F1 (10A) as protecting
- EGR control box (= EGR relay) #830
- Preheater (glowplug) relay (coil, not GP supply)
There is no mention of F1 supplying Immobiliser.

Turning to the circuit diagrams, it seems that
(a) EGR relay #830 was only fitted to LHD P8B/XUD11ATE engines (source 518-05/10, 10a...10c)
but
(b) fusing for this relay was repeatedly shifted across the XM fuseboards:
RP 6381-6568, fused at engine bay F1 **
RP 6568-6811, fused at engine bay F5
RP 6811-7084, fused at main board F31 and via main board SH (shorting link)
RP 7084-7252, ditto

For all
RHD P8B/XUD11ATE engines (source 518-24/10, 10a...10c)
LHD THY/2.5 engines (source 518-05/20, 20a...20d)
RHD THY/2.5 engines (source 518-25/20, 20a...20c)
(a) No EGR relay was fitted
(b) EGR recycling pump (vacuum pump) #759 had unfused supply, fed straight from IGN switch.


Conclusions
From the circuits, it appears that only some early LHD cars (** above) had fusing of the EGR relay ('control box') at engine bay F1.
I have not been able to identify how this fuse blowing could affect keypad/immobiliser, as they do not share supplies.
It's possible that JK's car wiring had been altered, or that the high current rush (which caused F1 to blow) also put strain on another connection (maybe a contact in the IGN switch), which threw up the Red+Green keypad fault.

Unfortunately, this probably sheds more light on EGR/Relay/Fusing arrangements than it does on keypad/immobiliser.

[xmexclusive]

All these comments refer to XM series 2 cars.
The XM series 1 cars are yet another set of wiring variations unfortunately without a set of ORGA dates to help pin things down.

Pull engine bay F1 on my R reg 2.5 and the keypad locks red green.
The wiring on that car though is an inherited mess that I am perhaps half way to sorting.
May continue with it though as it only need a windscreen and small outer sill plate for another years MOT.

John

[JK99]

WhiteExec wrote:
"It's possible that JK's car wiring had been altered, or that the high current rush (which caused F1 to blow) also put strain on another connection (maybe a contact in the IGN switch), which threw up the Red+Green keypad fault."

I now remember what the garage guy told me : that someone had messed with the wiring, and that the garage had therefore replaced it. I also mentioned to the garage that someone had advised me of a possible way to cure the problem; ie to insert a 40 amp fuse. I had not followed this advice, fortunately. The garage informed me that had I done so, the whole wiring would have fused.

So, for heaven's sake do not be tempted to replace the FI fuse with a higher rated fuse.
JK99

[Dieselman]

What does the injection Control unit relay (802) do? It takes a signal from te keypad and feeds +12v into the ECU on Pin 19. (taken from 12v diagram).

Other than signifying connection, is the keypad actually providing any signal tot eh ECU other than via the Injection Control relay? Does the ECU just monitor the last noown state of that relay contolled signal?

Has anyone got a Series 1 V6-24v circuit diagram for download?