Freelander 1 Auto 1.8

Looks like it yes. Would the Trinary switch fit into the same position as the pressure sensor? If the thresholds in the Trinary are ok it would save the work and circuitry.

For the Freelander
The upper pressure limit is 29 bar (421 lbf/in 2 ), e.g. due to a blockage. Compressor engagement is re-enabled
when the pressure decreases to 23 bar (334 lbf.in 2 ).
The lower pressure limit is 1.6 bar (23.2 lbf/in 2 ), e.g. due to a leak. Compressor engagement is re-enabled when
the pressure increases to 2.0 bar (29.0 lbf/in 2 ).

For the Rover 75

andyfreelandy said:

Looks like it yes. Would the Trinary switch fit into the same position as the pressure sensor? If the thresholds in the Trinary are ok it would save the work and circuitry.

Click to expand...

that's a much better idea than mine. Looking at pictures they look kind of similar.

If the Trinary in the Rover 75 uses the medium pressure switch to operate the condenser cooling fan, then does the Freelander derive the pressure for fan operation from the pressure sensor according to pressure seen represented by the voltage fed to the ECU by the pressure sensor?

So would need to make the Rover ECU operate the Condenser cooling fan when required if you need to retain the FL sensor.

I don't really understand how the Freelander 1 system works. However I can see that there are two fans and there seems to be a connector on each fan motor.
The Rover 75 system is much easier to understand, there are two ECU pins, one for low speed and one for high speed.

I'm tempted to re-wire it like my old Peugeot 305. On low speed it configured relays to put the fans in series so that they would get 6V each, and on high speed it configured the relays to put them in parallel so that they both get 12V.

Circuit shows the 2 in parallel driven by the controller which has a single wire control from ecu. I thought one fan was a/c condenser cooling only but circuits say not.

bad news. The petrol cluster isn't the same as a TD4 one. I connected an EVAP temp sensor to C0230-20 and monitored CANbus and it doesn't send the EVAP temp data over CANbus. Then I swapped in a TD4 cluster and it does.

So, I have asked Andy if he can modify the Rover 75 firmware (again) to pick up the sensor like a Freelander does.

Unless anyone knows anyone who knows how to modify Freelander clusters.

What's to stop you fitting a TD4 cluster ? It is similar in other functions I bet.

I might do that.

I can not get my Rover 75 ECU to pick the A/C switch input even when connected to a Rover 75 heap of ECUs (including a climate control ECU). So today I drove to Maidstone to meet Matt from the "Furious Driving" channel because he has a 1.8 75 with working A/C and he let me tap into the CANbus of his car and collect packets. From there I can hopefully emulate enough of an actual car to make the ECU work, and then from there figure out how it works.
He was asking me stuff whilst filming me so no doubt there'll be content. Maybe.

I appear in the last few minutes:-

I think I know what the problem is with triggering the A/C. Freelander instrument cluster sends 0x80 in B0 of 0x615 to turn on the A/C whereas Rover 75 sends 0x40.

some more progress.
I now have firmware for Rover 75 NNN000100 NNN000110 ECU that recognises the Freelander 1.8 Evap sensor, though it does involve repinning the wire from pin 47 to pin 10 (easy with a paperclip).
Next steps are that I need to fake the Rover 75 trinary switch, hook up the cooling fans in the 75 way, and emulate the 75 instrument panel CANbus output for A/C switch, and see if I can get the ECU to actually pull in the A/C compressor clutch.
Once I have done that the final challenge for Andrew is to hack the CANbus input for A/C switch and then I think all the electronics is done.

well.... except for hooking up a Jatco ECU of course

Tantalisingly close Philip!

andyfreelandy said:

What's to stop you fitting a TD4 cluster ? It is similar in other functions I bet.

Click to expand...

When I put my 1.8 petrol cluster into my td4 automatic all the functions (including auto messages) worked , but I couldn't check the AC as my Freelander AC needs a regas.
The main issue with using a td4 cluster is the rev counter has a lower scale.
Something I did consider had that test not worked was to use the V6 cluster as they were all auto and I suspect all had AC too.They have the same expanded rev counter scale the 1.8 have.

I don't think that I will need a TD4 cluster after all.
I now have an NNN000110 ECU that picks up the EVAP sensor directly (just like the stock Freelander ECU, though on pin 10 instead of 47) therefore I don't need to get it from the cluster.

Which model auto ECU are you planning to use?
From what I understand they are all(Freelander and r75) the same hardware but have differing firmwares to suit application and engines , this gives at least 5 variations!
I was thinking the V6 version should give higher shift change points then the td4 would perhaps?
I have both r75 and Freelander units , it will be interesting to see if the can codes and the steptronic options work (r75 doesn't have that on the selector)