Central locking/alarm problems

Hi People . been a long while since i was last on here , so apologies for my absence.
I have a central locking/alarm problem on my R reg D1 300tdi 5 door manual. . I have an electrical gremlin somewhere coming from tailgate wiring . I have replaced the door switch and not cured problem . When tailgate open I can unlock doors with fob and start the engine .. Now when the tailgate is shut , no central locking and cannot start the engine . I have checked the wiring in the flexible sleeve and its fine .. It is down to the white/purple wire that is on the door switch .. I have pressed in slowly and just before the door closes , the indicators are not constant flashing , but intermittent and not very bright and when door fully closed , the same poor intermittant flashing ..
Anyone help me out please . The cold weather now is affecting my health and mobility , and just about at wits end to find the problem ..
Thank you

First thing I would do, is disconnect the switch completely, insulate the spade connector and see if that at least gets you mobile..

Then I'd be extracting the door sw wire from the structure, to check its integrity..

I don't understand why this issue is preventing the vehicle starting though..

There's a joint in the cable in the passenger footwell which might have some issues - the location is detailed quite well in RAVE..

I've had issues in this area with my own 97 300Tdi, so I understand your frustration

Disco1BFG said:

First thing I would do, is disconnect the switch completely, insulate the spade connector and see if that at least gets you mobile..

Then I'd be extracting the door sw wire from the structure, to check its integrity..

I don't understand why this issue is preventing the vehicle starting though..

There's a joint in the cable in the passenger footwell which might have some issues - the location is detailed quite well in RAVE..

I've had issues in this area with my own 97 300Tdi, so I understand your frustration

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Hi , and thank you .. I have tried that ( disconnected spade and also put a new switch in ) Landy will start with the tailgate open and will run when tailgate shut . I am assuming because of the Central locking issue , it is connected to the immobiliser/alarm unit . Unfortunately for some reason . I cannot download RAVE onto this PC ( i just get a white screen , i tried so many times ) From what I can make out( haynes manual) the white purple wire is common to the central locking on all doors . I am thinking of just running a wire from the rear right door switch to the tailgate to see if that cures the problem ( if so i can just get the same colour awg wire and pull through and throw the old wire out ) . Having Osteio and Rhumatiod Arthritis is no joke and working in this weather is no joke .. now if it was in the 30's C it's a different matter lol.

I’m confused with you stating a “spade connector” with a central locking issue, only the door pin has a spade connector for alarm interior lighting and security switching via the multifunction, the locking actuators are fitted with a multi connector.
With any door open the actuator will still operate and you can still lock the close doors, it should be accompanied with a mis-lock beep from the alarm sounder indicating a door is not fully closed, the MFU knows the interior lights are illuminated so signals the security ECU to give the beep.

discool said:

I’m confused with you stating a “spade connector” with a central locking issue, only the door pin has a spade connector for alarm interior lighting and security switching via the multifunction, the locking actuators are fitted with a multi connector.
With any door open the actuator will still operate and you can still lock the close doors, it should be accompanied with a mis-lock beep from the alarm sounder indicating a door is not fully closed, the MFU knows the interior lights are illuminated so signals the security ECU to give the beep.

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The spade connector is on the actually door switch( courtesy light ) .. The central locking only works when the tailgate is open ( all 5 doors lock) but when tailgate is closed . no central locking . Vehicle will not start unless the tailgate is open . I have used the fob for C/L and it works when tailgate open.. when tailgate is nearly closed ( switch nearly pushed in ) C/L doesn't work and the indicators are struggling to flash . door open and indicators flash as normal.... because of the fiddling with the door switch , it seems that there may be a problem with the white/purple wire that is the door switch not correctly functioning , therefore it is not allowing the alarm to MFU to get a signal .. I am only guessing here as checked the wires in the loom ( body to tailgate )..... If there is a fault on the wire hence why the indicators are not getting constant voltage to flash correctly

Chris53 said:

Unfortunately for some reason . I cannot download RAVE onto this PC

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This is pretty weird IME, its simply a set of PDF files - which are indexed from the main start file..

I've tried to attach the D1 ETM, which should help, and be infinitely better than the Haynes..BUT, the forum is broken for some reason at the mo.. Presuming you have email, PM me, ( with your email address(!) ), and I can email it to you.. you might find it on the web - you're looking for LRL0077ENX 6th Edition..

What happens if you leave the wire disconnected ?

Have you searched for the well known Spider problems ? Do your issues sound familiar in this context ?

Have you had a new alternator recently ? If you've had a new alternator at any point, my own experience is that the voltage regulator has too high a set point, and will be cooking your MFU and alarm.. ( ask me how I know ).

Are your courtesy lights working normally ?

Will the MFU enter self test mode ?

Do you have diagnostics ?

Can they talk to the alarm system Ok?

Lots of questions, but.. I suspect one of the main relays in the alarm unit is failing - which can be fixed, but don't have enough info yet..

Disco1BFG said:

This is pretty weird IME, its simply a set of PDF files - which are indexed from the main start file..

I've tried to attach the D1 ETM, which should help, and be infinitely better than the Haynes..BUT, the forum is broken for some reason at the mo.. Presuming you have email, PM me, ( with your email address(!) ), and I can email it to you.. you might find it on the web - you're looking for LRL0077ENX 6th Edition..

What happens if you leave the wire disconnected ?

Have you searched for the well known Spider problems ? Do your issues sound familiar in this context ?

Have you had a new alternator recently ? If you've had a new alternator at any point, my own experience is that the voltage regulator has too high a set point, and will be cooking your MFU and alarm.. ( ask me how I know ).

Are your courtesy lights working normally ?

Will the MFU enter self test mode ?

Do you have diagnostics ?

Can they talk to the alarm system Ok?

Lots of questions, but.. I suspect one of the main relays in the alarm unit is failing - which can be fixed, but don't have enough info yet..

Click to expand...

I have had a Landrover specialist look at it and he has connected to the OBD etc and got the C/L and alarm working days ago . So starting etc is fine . He suspected a fault in the wiring loom ( the main loom that exits the body to the tail gate ). As I found that door open c/l worked and could start vehicle ... I pushed the door switch in slowly as i was pressing the fob and that is when I discovered the problem of the c/l not working correctly and the indicators failing to flash correctly .. So purchased a new switch and that didn't cure it ... I found the wiring in the haynes manual ( white purple) and noticed all the switches are using same color ( I haven't checked the diode for rear door as no idea where it is or looks like , if it has one ). then the wire continues to the alarm module , then 2 wires ( purple/white and purple/green go to the MFU ). I do have another wiring loom arriving soon so that I can take the old one out and try . I have ordered some white/purple wire so that if problems I can pull the new wire through .I will p.m my email addy to you

PM received and replied to, ETM sent..

The diode is in the passenger foot well - it's just a zener diode in some heat-shrink tubing..

If you could answer the other questions in post #6 it will help..

Did diagnostics show the door opening and closing ? Mine do - worth buying your own, they have come down in price enormously..

You're right about the connections to the MFU from the alarm, but my D1 no longer has an MFU - it went kaput, and they are not repairable or replaceable ( unless you think £300 is worth a punt - cos they're all 20+ years old now )..

OMO, but be careful with the MFU for the above reasons..

The alarm was fitted to many austin rover vehicles of the period, and is repairable..

Have you replaced a door hinge recently ? I've seen the door loom get caught, with weird, but fairly obvious consequences..

Disco1BFG said:

PM received and replied to, ETM sent..

The diode is in the passenger foot well - it's just a zener diode in some heat-shrink tubing..

If you could answer the other questions in post #6 it will help..

Did diagnostics show the door opening and closing ? Mine do - worth buying your own, they have come down in price enormously..

You're right about the connections to the MFU from the alarm, but my D1 no longer has an MFU - it went kaput, and they are not repairable or replaceable ( unless you think £300 is worth a punt - cos they're all 20+ years old now )..

OMO, but be careful with the MFU for the above reasons..

The alarm was fitted to many austin rover vehicles of the period, and is repairable..

Have you replaced a door hinge recently ? I've seen the door loom get caught, with weird, but fairly obvious consequences..

Click to expand...

. Hi Bud .. I did answer .. .. both alts been on for months ( i have 2 ) .. wire disconnected = same as having door shut ( that is why i believe wire is faulty) .. No problems with spider , yes courtesy lights are working etc all round .. ( no idea what MFU self test is or how to do it ).. Diagnostics done 4 days ago ( after got C/L working. that is when we found problem with rear switch ).. Alarm system ok . as when fob locks the indicators flash normally ..... it is just when the tailgate is ajar that the C/l and alarm does not work correctly )