Topic

Hi,
I have started to use the PSCAN tool, I have cleared all existing faults. It was an interesting indication of work that was previously carried out on the car. I have then looked at the errors that have reoccurred.
Two seem to have been indicated with no description
P025D and P0535 both with the following code J1979 Unknown. Which I think is industry standard for unassigned faults.

Can anybody clarify possible causes.

I also have a P0462 Fuel tank level circuit issue. Which I was expecting as the tank level doesn't drop until I have used 1/4 tank. Something I can live with at the moment.

which ECU are you referring to?

Main ECU I think under Mems 3.0 MGTF LE500.
I think one of them may be to do with fuel, but not what/ why.

Occasionally there is a check sum error reported as well. I know why/ what it is but am unsure if this is common.

I will need to recreate these fault code in the lab environment and get back to you.

I wonder whether there is any resolution to these codes as mentioned in this thread as I have the same codes on my car except from P025D? I have a MGTF 85 Anniversary edition which apart from minor differences is the same as the LE500. Despite clearing codes, 3 codes keep reappearing P0535 J1979 unknown, P0462 fuel tank level input circuit fault, and P0601 internal control module memory check sum error. The car runs fine with no warning lights on, however I would like to know how to permanently rectify the issues so I don't constantly have these codes coming up.

I think all codes are referring to the fuel.
I just don't know what.
I think the J1979 is a catch all code for fuel codes which haven't been adopted by the industry.
I am going to service the car (when the weather warms up), I am going to change the fuel filter as well as the normal things.
Checksum errors are a Computer method to check calculations, It is if I remember correctly looking for an even number of bits to ensure calcs are working. Why it is returning this I don't know. It could be programming or a fault in the system.

The logic in the code is thus:-

If we know the MG Rover proprietary meaning for a code then we give you that.
If not, but there is an "industry standard" meaning for the the code then we give you that, prefixed with J1979.
If not, then we give you the code with the text "unknown" as the meaning.

SAE J1979 is the international standard for error codes and this is what a generic EOBD/OBD2 scanner would give you.
A huge proportion of MG Rover codes have the same meaning as J1979 and so I think that this makes sense, but if you see J1979 then it does indicate a hole in our knowledge and therefore room for improvement.

I am not in a position to help with specific codes for a few weeks I'm afraid.

Hi,

I have a TF135 with the N series engine as well. (Continental ECU , MEMS3.)

I also have had the same codes for some time. P0462, P025D, P0535, and after a remap I then also got P0601 Memory Checksum error as well.

When I trawled the forums etc they seemed to be normal for SAIC MG135 / Continental ECU

Cheers, Mark