P0125 & some more

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kaz

5/12/2008 10:09:05 AM

Still buying..
Yesterday I looked at model '96 with intermmitant P0125, as per owner.
He wasn't forthcoming with the info, was just, most likely, hopeing CE light won't come while I drive it. But it did and he then told me about the error, saying it happens when car is cold and then goes away.
From what I read so far it looks like 'flaky' ECU due to a PROM which is NLA.
I'm in industrial & consumer electronics service field and quite often deal with corrupted PROMs,EPROMs, EEPROMs etc.
In my field there are 'dump libraries' with the files that one can use to 'burn ' a new chip.
I came across similar libraries for cars, dealing mostly with 'upgrading' ECU (changing PROM/EPROM content, and for unlocking radio codes.
Looks to me that in this case NLA PROM issue could be easily resolved by coping its content from model '97 (as I understand with upgraded version that resolves P0125) and burning a new chip to be installed in affected car..
Hasn't anybody done that so far?
I know some times equipment manufactures (I guess car inustry included), erase the generic # of the chip to make identification difficult/impossible.
Is this a case here?, if someone tells me chip generic # off the '97 model, I could most likely asses if coping is possible, and if yes I could burn a chip.
At the end I have a question, about rust. I read somewhere that one should stay away from a LR displaying sign of rust in know arears. I've seen a few Discos1 with tuches of rust, especially around back door close to belt anchor. Nothing big that half an hour with a torch wouldn't resolve. Or is it a predictor of rust in places that I cannot see and it spells a lot of trouble in the (near?) future?
I posted it on discoweb as well, I hope it doesn't spell trouble for me..

Disco Mike

5/12/2008 11:08:59 AM

P0125 is a Insufficient coolant temperature for Closed Loop Fuel Control,
has nothing to do with the above mentioned post.

roverguy7

5/12/2008 3:46:30 PM

actually it definitly does. there is a tsb about replacing the prom in your ecm for this code, of course you should make sure that its not a fault with the sensor, or cooling system first, but yeah, its generally the tune... however, i can get you the rover part number for it, but as to copying it, i have no idea man

Disco Mike

5/12/2008 4:15:27 PM

Learn something new every day.

kaz

5/12/2008 5:10:39 PM

LR part # won't actually help, most likley it has no association with the generic number on the chip, and thats the one I need.
I'm hopeing somone may have a ECU for '97 or '98 in the bone pile and could have a look and tell me what is on the chip.

Spike555

5/12/2008 6:36:04 PM

As for the rust, I know the spot that you are talking about, mine is doing the same thing. There is a seam there and salt collects there, wash it really well, sand it and paint it, undercoat and then you should be good.
I need to use fiberglass on mine, it rusted trough.

roverguy7

5/12/2008 7:58:10 PM

once again, dont know about what exactly youre going to do here, but the rover part is updated, not the original one that came with the car, its the update that will take care of this issue, if it makes a difference

kaz

5/13/2008 3:20:00 AM

quote:

ORIGINAL: roverguy7

once again, dont know about what exactly youre going to do here, but the rover part is updated, not the original one that came with the car, its the update that will take care of this issue, if it makes a difference

OK, so part is not NLA, the modified PROM?, what is the part # and do you know the source?
Thanks.

kaz

5/13/2008 7:05:28 PM

I was refering to the below bulletin:

quote:

12/06/96
19/08/96/US
SUBJECT:
PRIDE - GEMS Code P0125
MODEL:
Discovery
Discovery
Discovery
AFFECTED VEHICLES:
LP
LJ TA163104 to TA200000
LJ TA501920 to VA534107
LJ TA700000 to VA703240
DETAIL
Vehicles equipped with GEMS may store P code P0125 in the ECM. This code may be stored by a number of reasons. Follow the details below for guidance.
The diagnostic steps and repair procedures detailed in this bulletin were developed as an element of the Land Rover Way Operation PRIDE. This TIB provides a library location for PRIDE information within the Land Rover North America technical literature system.
ACTION REQUIRED
If diagnostic trouble code P0125 is retrieved during TestBook diagnosis, follow the diagnostic procedure below.
PARTS INFORMATION
PRM9631 - PROM Set
Removal

1. Make sure that the ignition key is turned off.
2. Remove washer reservoir and set aside.
3. Remove ECM cover using suitable tool to remove clips.

NOTE: Ensure that the white anti-backout strips have not fallen out of the connectors. If so, replace them in the connectors.
4. Unplug the ECM connectors. Remove ECM.

5. Place ECM, red connector side up, on grounded antistatic mat. Be sure to wear grounding wrist band.
6. Remove five Torx(R) screws (t2O) from cover, and remove red connector side.
NOTE: Circuit board is easily damaged. Do not pry covers off using screwdrivers or the like.
7. Remove 8 Torx(R) screws holding circuit board.

8. Fold circuit board over onto mat, exposing chips .

9. Using suitable pliers, carefully remove blue and green PROM covers .
10. Remove the exposed PROM with PROM puller supplied with anti-static mat.

Make sure that the notch on the PROMs are in line with the notch on the PROM sockets. PROM notch will be oriented towards the red connector.
1. Carefully install new PROMs, noting that one PROM has 28 pins and the other 32 pins.
2. Check for bent pins before replacing PROM covers.
3. Position circuit board and fasten with screws.
4. Install outer cover. Fasten with screws removed earlier. Torque to 2.25-2.82 Nm (20-25 lb. in).
5. Apply the self-adhesive update label on the side of the ECM to signify that the update has been done.
6. Reconnect wire harnesses and install ECM.

7. Install ECM protective cover and washer reservoir.

VERIFICATION AND ROADTEST
A. Switch on ignition. The fuel pump should run for a short period. Listen for any unusual noises such as injectors operating or relays clicking which would indicate a problem.
B. Observe that the Check Engine light comes on and stays on during the bulb check. If not, check the multiple connection. If necessary, replace the ECM.

C. If the vehicle fails steps A or B, recheck the multiple connector pins and socket. If this does not resolve the problem, check that the PROM was installed correctly.
8. Perform quality check procedure below.
QUALITY CHECK PROCEDURE
Start engine and observe the following:
1. The Check Engine light remains out.
2. Idle speed smoothness is stabilized.
3. Switch on A/C, and note idle speed compensation.
4. Rev the engine; no misfire should be noted.
5. Select drive and note idle speed compensation - automatic only (brakes applied).
9. Roadtest the vehicle (drive cycle B per service bulletin W96-007).