RangeRovers.net Forum banner

1 - 19 of 19 Posts

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #1
Just purchased a P38 and the car starts and runs fine, but seemingly all components controlled by BeCM are not working. I swapped a new power board from another BeCM and the symptoms are exactly the same. All fuses on the BeCM are intact. HVAC and radio turn on and operate, but I'm not sure if those are tied to BeCM. Any help would be appreciated.
 

·
Administrator
Joined
·
27,834 Posts
Year? Model?

Windows and sunroof obviously share the switchpack. Seats could be a seperate issue. Add to that the miriad of grounds to check and various power feeds from under the hood I would start checking the schematics for a unified source like a maxi fuse or duff feed from the underhood fuse box.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #3 (Edited)
It is a 98 4.0SE. Looks like relay 7 is slightly charred and shows some melting on the fuse box. Would this have anything to do with the issue? Where should I start with the electrical diagnostic process if I have no previous experience? Is all the information I need in RAVE?
 

·
LEGACY VENDOR
1995-2002 Range Rover P38A
Joined
·
4,225 Posts
RAVE has pretty much everything you need to know about these vehicles...

If your fuse box is looking like it's crispy or melting, then I would just replace it now, before it causes any other problems... It could be something has melted in the fuse box which is stopping the supply of power to the BECM.

Have you looked under any of the other relays/fuses in there to see if there's any other visible signs of damage?

RL7 is a common fault area - as it controls one of the blower motors - RL6 does the other. If it is discoloured/melting etc, then it shows higher than normal load on the blower motor, so checking the pollen filters would be wise...

RAVE has electrical troubleshooting manuals, which will help you trace where the BECM draws it's power from, and should help in tracing fuses, wiring etc.

Cheers,
Marty
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #5
I swapped the donor BeCM that I pulled the power board from into the my P38 and the power seats, windows, etc were all operable but the car would not start due to the logic board not communicating with the engine ecu. Clearly the original BeCM has an issue but it is not related to the power board. I'm not familiar with issues related to the logic board. Do I have any options, or will I have to replace the BeCM and have it reprogrammed to match the car?
 

·
Registered
Joined
·
931 Posts
I swapped the donor BeCM that I pulled the power board from into the my P38 and the power seats, windows, etc were all operable but the car would not start due to the logic board not communicating with the engine ecu. Clearly the original BeCM has an issue but it is not related to the power board. I'm not familiar with issues related to the logic board. Do I have any options, or will I have to replace the BeCM and have it reprogrammed to match the car?
I think yours is a GEMS system.To get the engine to start with the new BECM you will need a Diagnostic tool able to put the GEMS ecu into the security learn mode.This will enable the ECU to learn the code in the new BECM.However if you do this then your key fobs will not work with the new BECM.The BECM will have to be Unlocked (software) and you will need the three part fob code to then reprogram this code into the unlocked BECM to enable the fobs again.

Also any other settings in the new BECM will need to be set to the correct setting for your RR.IE as per your old BECM.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,219 Posts
Gotta agre with the posters that have suggested replacing the fuse box. I had several intermittent problems, sunroof and windows not closing, odd messages on the message centre and bad starting. All cured with a new fusebox, oddly, mine looked absolutely fine when taken out.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,851 Posts
Hi

After synchronizing the new BECM with the engine ecu the car will probably run ok but the keys remote control unit will not work. If you have the key fobs from the car you got the BECM from then you could take your key fob apart and exchange the internals or the key part. After that you can run with the new BECm without any problems.

I know of several cars here that are running with non original BECMs. There is of course a mismatch of the programmed VIN in your new BECM and the car it is used in but that will only come to light when the car is connected to a diagnostic computer.

Best regards

Jos
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #9
I think yours is a GEMS system.To get the engine to start with the new BECM you will need a Diagnostic tool able to put the GEMS ecu into the security learn mode.This will enable the ECU to learn the code in the new BECM.However if you do this then your key fobs will not work with the new BECM.The BECM will have to be Unlocked (software) and you will need the three part fob code to then reprogram this code into the unlocked BECM to enable the fobs again.

Also any other settings in the new BECM will need to be set to the correct setting for your RR.IE as per your old BECM.
So if I were to buy a faultmate I could put the GEMS ecu in to security learn mode and then the car would start from then on? I don't currently have any keyfobs for the car so I'm not too concerned about that issue. What other settings are you referring to needing to be set? Also, are there any other issues I should be aware of with going this route as opposed to getting a new BeCM programmed with the logic for my car?

Thanks for the help.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,851 Posts
Hi

If you buy a faultmate you would be able to set everything in your new BECM to your liking.
Your registration of the faultmate will be under the VIN of the BECM.

In the BECM you can set all kind of parameters if you are curious about what have a search in the diagnostic forum and at the BBS web site.

Regards

Jos
 

·
JACK'S GRANDAD
Joined
·
9,248 Posts
The becm is locked when the dealer gets it normally. So Faultmate will NOT do what you need.
Scotty has the correct module to unlock the becm, program your vin number, mileage, fob codes, and so on. Basically, send him you info and the donor becm, or to be safe send him both becm's so an exact copy can be made.
I have Faultmate etc, but when my becm went into lockdown, it was useless.
By far the cheapest way to do it right, and never have issues again. The bonus is, he will leave the becm unlocked to future issues wont stop you dead if you have a Faultmate for your rig.

Martin
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,851 Posts
Hi again

If your replacement BECM is set to the Diesel and you are driving a 4.0 or 4.6 the engine will not start. If the BECM is set to a bosch system and you have a GEMS there will also be no starting. You will be able to set everything to match your car with the faultmate and synchronize the BECM and engine ECU.

Regards

Jos
 

·
JACK'S GRANDAD
Joined
·
9,248 Posts
Maybe a NAS thing Jos?
I know that Scotty is doing a fair trade in replacement Becms with the SM035 module.
I know when mine went into lockdown, the Faultmate would not do a thing to it, as it was locked from the originating dealer here in the USA. Once unlocked though, it went into relearn and sorted itself out.
No diesels over here, so that isn't an issue, but there are quite a few settings that cannot be changed with the "normal" Faultmate over here. VIN, Mileage, and so on.
I highly doubt it would work, and would hate for the OP to set a Faultmate up for a Becm that doesn't work!
I know Carl and Scotty know more about the inards of the becm than most, so maybe they will chime in soon...

Martin

PS, Many thanks to your write up on the carbon brushes (I used teh search function believe it or not!), I currently have one apart and am on the search for new brushes:thumb:
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
1,851 Posts
Hi Martin

I remember reading about your BECM problems. If the unit is in lock down I assume it gives a message and there is indeed no alternative then to sent your unit to get it unlocked. There are many halfcuts P38 imported from Japan over here in Malaysia and I have seen that workshops here implant BECM's from these half cuts into cars with BECM problems and get them to run and even use the key fobs of the half cuts to lock and unlock the cars.

About the carbon brushes, I assume you are referring to the blowers. It was one of my first problems with the car (After EAS fault) back in 2002 when I bought it and I have since repaired a few motors by replacing the brushes. I was helped so much by the info on rangerovers.net that I normally post details on repairs that have not been covered.

Regards

Jos
 

·
JACK'S GRANDAD
Joined
·
9,248 Posts
Yes the blower motors mate.
Will try to find new brushes and see what happens! Worth a couple of $$$ for sure IMHO.

Martin
 

·
Registered
Joined
·
931 Posts
The becm is locked when the dealer gets it normally. So Faultmate will NOT do what you need.
Scotty has the correct module to unlock the becm, program your vin number, mileage, fob codes, and so on. Basically, send him you info and the donor becm, or to be safe send him both becm's so an exact copy can be made.
I have Faultmate etc, but when my becm went into lockdown, it was useless.
By far the cheapest way to do it right, and never have issues again. The bonus is, he will leave the becm unlocked to future issues wont stop you dead if you have a Faultmate for your rig.

Martin

Martin,my post no 6 covered these issues in getting a replacement BECM to work.You do not need to unlock it to program the BECM and Engine ECU to sync.If as in your case the BECM went into "lockout" you do then need to unlock with Sm035 in order to reset it to use it again.
You do however have to unlock it if you wish the original Fobs to work with the replacement BECM.
Hope this helps to clarify it .
By the way the Dealer normally gets a UNlocked BECM.So they can program completely and then "lock" it using testbook.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #17
Just wanted to close the loop on this thread and let anyone with similar issues know that I resolved the problem by getting a working becm and engine ecu combo from another gems 4.0 range rover. Transplanted them in to my rover and everything is working well.
 

·
Administrator
Joined
·
27,834 Posts
What about your key remotes? What about your odometer? What about your recorded VIN? Headlight, wiper, DRL, one touch, window pack, sunroof settings?

Your remotes have a unique three digit code that must be programmed to the BeCM. Your VIN is specific to the BeCM. Your odometer reading in the cluster needs to match the odo in your BeCM programming. Other custom settings you had previously are no longer going to be present.

Your rig may very well start and run, but I can guarantee "everything is working well" it is not as simple as snagging a BeCM/ECM pair out of a junk yard.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
12 Posts
Discussion Starter #19
What about your key remotes? What about your odometer? What about your recorded VIN? Headlight, wiper, DRL, one touch, window pack, sunroof settings?

Your remotes have a unique three digit code that must be programmed to the BeCM. Your VIN is specific to the BeCM. Your odometer reading in the cluster needs to match the odo in your BeCM programming. Other custom settings you had previously are no longer going to be present.

Your rig may very well start and run, but I can guarantee "everything is working well" it is not as simple as snagging a BeCM/ECM pair out of a junk yard.
I have not had the keyfobs since I purchased the car so I wasn't specifically worried about that, although I know it is not smart to be without them. Odometer is working perfectly, no errors. I am assuming that is because the stored mileage on my rover is higher than the stored mileage on the new BeCM. Window switchpack, headlights, and power seats are all working again.

I guess the caveat should be clear, this is not the optimal solution I just wanted to make everyone aware that I obtained the BeCM/ECU from an indentical model and it seems to have worked without any errors that I have noticed so far. What custom setting are you referring to so I know what to look for.
 
1 - 19 of 19 Posts
Top