Hi,
Are there any other Freelander 1 diesel owners out there who would like to "talk" to their car via the diagnostics port?
I've just bought a 1999 Freelander with the XDi (L Series) engine which has a "surging" idle so I've been checking for any obvious faults using advice from this forum. I then decided to have a go and try to check out the OBD port for faults using a laptop PC.
I have done a lot of research on the Freelander engine management system and realise that you can't just plug in a common OBD scanner (cos the protocol is pre-OBD). I then came across a website explaining the ISO9141 protocol (which the Freelander L series is supposed to use - according to the RAVE CD anyway). "Great", I thought, now we're in business...but unfortunately we were not...
I then re-read Rover Ron's website where on one page of the website concerning the L series diesel he says:-
"I also found out why diy and generic code readers don't work with the L series. I.E. why only mode 1 commands are recognised. Its because the ecu requires the code reader to request security access (mode 27). When it does so, it receives a seed which is converted by an algorithm within the code reader into a key. This is sent to the ecu which compares it with its own calculated key and if they match, access is granted. The seed is generated randomly at each access request. Once access is granted, the standard diagnostic modes work and some Rover specific ones are also used to test actuators and display more advanced sensor data. Eg fuel quantity, % egr flow, tps voltage, sensor supply voltage etc. The ecu also uses in-frame responses - which no ELM chip based scan tool support. (The Elm chip is limited to 7 data bytes)..."
My question to Ron is: How do you get the ECU to respond? What do you mean by "Mode 1 commands" or "Mode 27"..? I have plugged in my PC (and simple level converter - not an ELM chip) running RealTerm software at 5 baud and tried sending different "Init" codes to wake up the ECU (ISO9141 says it should be 33 Hex but I got no response at all from the ECU). I realise I won't be able to alter anything in the ECU but it would be nice just to be able to read basic fault code data!
I will keep you posted if I get any further with this or if Ron is able to shed some light on the ECU initialisation method, but in the meantime please let me know if you have any similar stories...
Cheers,
Are there any other Freelander 1 diesel owners out there who would like to "talk" to their car via the diagnostics port?
I've just bought a 1999 Freelander with the XDi (L Series) engine which has a "surging" idle so I've been checking for any obvious faults using advice from this forum. I then decided to have a go and try to check out the OBD port for faults using a laptop PC.
I have done a lot of research on the Freelander engine management system and realise that you can't just plug in a common OBD scanner (cos the protocol is pre-OBD). I then came across a website explaining the ISO9141 protocol (which the Freelander L series is supposed to use - according to the RAVE CD anyway). "Great", I thought, now we're in business...but unfortunately we were not...
I then re-read Rover Ron's website where on one page of the website concerning the L series diesel he says:-
"I also found out why diy and generic code readers don't work with the L series. I.E. why only mode 1 commands are recognised. Its because the ecu requires the code reader to request security access (mode 27). When it does so, it receives a seed which is converted by an algorithm within the code reader into a key. This is sent to the ecu which compares it with its own calculated key and if they match, access is granted. The seed is generated randomly at each access request. Once access is granted, the standard diagnostic modes work and some Rover specific ones are also used to test actuators and display more advanced sensor data. Eg fuel quantity, % egr flow, tps voltage, sensor supply voltage etc. The ecu also uses in-frame responses - which no ELM chip based scan tool support. (The Elm chip is limited to 7 data bytes)..."
My question to Ron is: How do you get the ECU to respond? What do you mean by "Mode 1 commands" or "Mode 27"..? I have plugged in my PC (and simple level converter - not an ELM chip) running RealTerm software at 5 baud and tried sending different "Init" codes to wake up the ECU (ISO9141 says it should be 33 Hex but I got no response at all from the ECU). I realise I won't be able to alter anything in the ECU but it would be nice just to be able to read basic fault code data!
I will keep you posted if I get any further with this or if Ron is able to shed some light on the ECU initialisation method, but in the meantime please let me know if you have any similar stories...
Cheers,
Martin
