P38 dse engine disabled

Hi guys,

I'm having an issue with my p38 2.5dse from 1998 LHD. During the past year or 2 I have been restoring her to get her back on the road. That went well I now got new registration.

In the meanwhile however it broke down with a faulty transfer case but that's not the culprit right now.

Because of a lower charging voltage I decided to replace the rectifier with a mobiletron rectifier. That means disconnecting the battery. So after installing it the car fired up straight away and charging voltage goes up to 14.5vdc.

However the days following the installation I noticed the keyfob didn't work as good as it did before, till the point it stopped working altogether to open or close the car. To open the car I started using the driver side key lock which worked until today.

I can still open or close the drivers side door but all other doors remain closed ( I can open them manually from inside), which means it is not superlocked? Once you open the drivers door the alarm goes off ( I disconnected the buzzer for now). Also the car won't start and says engine defect.

Before all this the BECM was programmed with the immobilizer disabled as is the EKA. If I try to connect to the becm with nanocom it is impossible to get into diagnostic mode ( not visible on the dashboard) or make any changes to the settings ( you can make changes but it doesn't get saved if you write to memory). All that was previously possible without issues.

When I disconnect the battery for a while and I reconnect it again, the car locks all doors (when opened manually from the inside) and becomes armed. (blinking flachers and buzzer upon opening the drivers door).


So I'm a bit in a predicament here, Is it right to think the drivers door lock mechanisms failed making the becm think it is still locked therefore prevent starting the engine?

Also why did the keyfob stop working (receiver?) Just to have some kind of direction before throwing parts at it.

When reconnecting the battery, it should resume the same locked-unlocked state it was in when disconnecting. Therefore always disconnect the battery with the car unlocked. Then lock manually using the door buttons if required.

Nanocom BECM mode only works with ignition off. Does it connect to other ECU's when ignition is on ? If not, check the diagnostic socket & footwell connectors for corrosion.

Yes it could also be the driver's door latch microswitches. If you cannot get the Nanocm BECM mode working, there's a how-to in the technical archive how to check them with a multimeter, but you need to take the door card off.

Update your forum profile with your town name. Might be other's nearby that can help.

Is the battery in the FOB OK?
It sounds like the EDC/BECM have lost sync.

Datatek said:

Is the battery in the FOB OK?
It sounds like the EDC/BECM have lost sync.

Click to expand...

Battery is new on both keys and they have worked ever since. I encountered an out of sync EDC before but this is not the same. In that instance I could easily go in and change the code via diagnostic mode. In this case the becm does not allow me to make changes.

pwood999 said:

When reconnecting the battery, it should resume the same locked-unlocked state it was in when disconnecting. Therefore always disconnect the battery with the car unlocked. Then lock manually using the door buttons if required.

Nanocom BECM mode only works with ignition off. Does it connect to other ECU's when ignition is on ? If not, check the diagnostic socket & footwell connectors for corrosion.

Yes it could also be the driver's door latch microswitches. If you cannot get the Nanocm BECM mode working, there's a how-to in the technical archive how to check them with a multimeter, but you need to take the door card off.

Update your forum profile with your town name. Might be other's nearby that can help.

Click to expand...

The problem is i cannot change the state of things , locked or unlocked. The car seems to return to its locked state , because it seems that the car the drivers lock is still closed.

I've taken the door card of, I've reset the windows and sunroof so outstation must be good. Also when I try to go to diagnostic mode I can make changes but not save them. But it also seems that all settings are wrong, wrong engine type , wrong ems code wrong market etc

pwood999 said:

When reconnecting the battery, it should resume the same locked-unlocked state it was in when disconnecting. Therefore always disconnect the battery with the car unlocked. Then lock manually using the door buttons if required.

Nanocom BECM mode only works with ignition off. Does it connect to other ECU's when ignition is on ? If not, check the diagnostic socket & footwell connectors for corrosion.

Yes it could also be the driver's door latch microswitches. If you cannot get the Nanocm BECM mode working, there's a how-to in the technical archive how to check them with a multimeter, but you need to take the door card off.

Update your forum profile with your town name. Might be other's nearby that can help.

Click to expand...

oh and I'm from Belgium so I think that's a bit far away

How do you disconnect the rod from the keylock, it looks like a clip is securing the rod in place?

BDC said:

The problem is i cannot change the state of things , locked or unlocked. The car seems to return to its locked state , because it seems that the car the drivers lock is still closed.

I've taken the door card of, I've reset the windows and sunroof so outstation must be good. Also when I try to go to diagnostic mode I can make changes but not save them. But it also seems that all settings are wrong, wrong engine type , wrong ems code wrong market etc

Click to expand...

All those setting changing is something that can happen with a low battery.

BDC said:

How do you disconnect the rod from the keylock, it looks like a clip is securing the rod in place?

Click to expand...

Yes there is a clip.

If i sit inside my car n lock it with the fob from inside ,then try to start it i get engine disabled .if i open with the fob still inside ,it will start ,,,,so if it thinks its locked you will get engine disabled , if that helps ..

Datatek said:

Is the battery in the FOB OK?
It sounds like the EDC/BECM have lost sync.

Click to expand...

Said engine disabled so thinking EKA has re-enabled itself somehow. Possibly RF interface caused volts to drop too low and BECM scrambled itself.

Fob batteries definitely worth checking, although I have never changed mine and I have had the car well over a decade.

BDC said:

oh and I'm from Belgium so I think that's a bit far away

Click to expand...

We do have mainland continental members but you are right in that they're more spread out.

Grrrrrr said:

Said engine disabled so thinking EKA has re-enabled itself somehow. Possibly RF interface caused volts to drop too low and BECM scrambled itself.

Fob batteries definitely worth checking, although I have never changed mine and I have had the car well over a decade.

Click to expand...

Engine Disabled does not mean EKA or immobiliser has somehow been re-enabled, it can come up if the BECM thinks the car is locked and you try to start it.

Yesterday evening I measured supply voltage to the rf receiver and that’s ok. It is fused by F15 at becm. I also verified F9 and F22, they all check out fine.

The door locks mechanically with the key but the motor is not working so cdl not working. I can hear it anymore. Hence I think the car thinks it’s locked. Normally I think the keyfob can be synced using the doorlock or Rf receiver. Neither work anymore. I’m thinking to replace the Rf receiver and the doorlock, maybe first try with a second hand one. If it works I’ll be replacing both front door locks.
It says engine disabled but also displays a message to press the fob.
I’m not entirely excluding the batteries although they have been replaced not all that long ago.

You need the both CDL & Keyswitch working to sync the fob. MGF latches are usually cheaper, but make sure you get the version with three microswitches.

Rimmers have new LHD drivers latches for £46 which is usually cheaper than second hand on eBay. Maybe cheaper for outside the UK ?

If you don’t mind can you share the link for the MG locks?

ignore my question you already did

pwood999 said:

You need the both CDL & Keyswitch working to sync the fob. MGF latches are usually cheaper, but make sure you get the version with three microswitches.

Rimmers have new LHD drivers latches for £46 which is usually cheaper than second hand on eBay. Maybe cheaper for outside the UK ?

Click to expand...

I ordered one from Rimmer bros today, it’s on it’s way. I’ll keep you posted. Thanks for the tip on the MG part compatibility