There is a switch on the throttle too.

This from RAVE Manual.
Throttle Pedal Switch

The throttle pedal switch is located at the top of the pedal box and secured in a cut-out hole in the fabrication. The switch is a proximity type Hall effect switch which senses a target located on the throttle pedal. The switch is connected on a single wire to pin 77 of ECM connector C0913.

The switch is normally open when the throttle pedal is at rest. When the throttle pedal is depressed, the target on the pedal moves away from the switch causing the switch to close and complete an earth path from the ECM. This is sensed by the ECM which uses the signal as a throttle status to detect for stuck throttle when using Hill Descent Control (HDC). The pedal status is compared with the inputs from the TP sensor to confirm that the throttle
is being depressed.

If the accelerator pedal position sensor input is missing, or the TP sensor input is implausible, the ECM inhibits the
throttle angle message on the CAN bus, which disables the Hill Descent Control (HDC) function of the ABS modulator
 
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There is a switch on the throttle too.

This from RAVE Manual.
Throttle Pedal Switch

The throttle pedal switch is located at the top of the pedal box and secured in a cut-out hole in the fabrication. The switch is a proximity type Hall effect switch which senses a target located on the throttle pedal. The switch is connected on a single wire to pin 77 of ECM connector C0913.

The switch is normally open when the throttle pedal is at rest. When the throttle pedal is depressed, the target on the pedal moves away from the switch causing the switch to close and complete an earth path from the ECM. This is sensed by the ECM which uses the signal as a throttle status to detect for stuck throttle when using Hill Descent Control (HDC). The pedal status is compared with the inputs from the TP sensor to confirm that the throttle
is being depressed.

If the accelerator pedal position sensor input is missing, or the TP sensor input is implausible, the ECM inhibits the
throttle angle message on the CAN bus, which disables the Hill Descent Control (HDC) function of the ABS modulator
I think that you have figured it out. C0913 pin 77 doesn't appear in a the Rover 75 wiring diagram and I don't see a throttle pedal switch either.
 
I made some progress today

This is a Rover 75 MEMS3 from an 1.8 auto running in the Freelander 1.8



As soon as I touch the accelerator pedal I get a hill descent error light on the dash though.

Throttle position and engine revs are coming though to the ABS ECU

r75ecuinfl12.png


r75ecuinfl11.png

Presumably HDC is being thrown because "Gear Selection" is "Undefined". ABS and TC do not need to know what gear the vehicle is in, where as HDC only works in 1st and reverse.
 
That's where I went GG. But I think these go straight to ABS module so changing ECU shouldn't affect this on the F1.

@pscan.eu how did you overcome the immobiliser code difference between the immobiliser ecu and the engine ecu ??

If you've cracked that we might be well on the way to making key chips !!
 
I made some progress today

This is a Rover 75 MEMS3 from an 1.8 auto running in the Freelander 1.8



As soon as I touch the accelerator pedal I get a hill descent error light on the dash though.

Throttle position and engine revs are coming though to the ABS ECU

r75ecuinfl12.png


r75ecuinfl11.png

I don't know if it helps but when I was testing prior to starting my EV build I found the CAN signal that turns on HDC.
I have the details on page one of the EV build thread.
 
how did you overcome the immobiliser code difference between the immobiliser ecu and the engine ecu ??

If you've cracked that we might be well on the way to making key chips !!

I had help from Andrew Revill ( https://andrewrevill.co.uk/ )

The immo and keys are all unmodified.

The R75 MEMS3 engine ECU is modified to:-
A: accept crank timing from an electronic box that converts from a PG1 crank sensor to a signal that the Rover 75 ECU can accept (with modification).
B: it ignores the signal from the SAWDOC / EWS3D immobiliser.

The vehicle is still secured to some extent by the immo, but not by the engine ECU anymore.
 
I don't know if it helps but when I was testing prior to starting my EV build I found the CAN signal that turns on HDC.
I have the details on page one of the EV build thread.

I think that you mean these posts?
https://www.landyzone.co.uk/land-rover/freelander-ev.360880/page-7#post-4920960
and
https://www.landyzone.co.uk/land-rover/freelander-ev.360880/post-4902890

My feeling is that the engine ECU is sending both the throttle switch status (that's unique to Freelander) and throttle position sensor reading over CANbus to the ABS controller. If the ABS controller sees any throttle sensor reading more than 0% without the switch changing first then it disables hill descent.
 
can anyone absolutely, definitively tell me whether the IRD on our late model 1.8 is going to work with a pre-facelift V6 automatic gearbox?
One person told me that the IRDs are all the same, another has told me that the V6 ones are different and not compatible.
I have a possibility of getting a used automatic gearbox, but I'm wondering whether that's enough or whether I need the entire drivetrain (IRD, rear diff, drive shafts)?
 
can anyone absolutely, definitively tell me whether the IRD on our late model 1.8 is going to work with a pre-facelift V6 automatic gearbox?
One person told me that the IRDs are all the same, another has told me that the V6 ones are different and not compatible.
I have a possibility of getting a used automatic gearbox, but I'm wondering whether that's enough or whether I need the entire drivetrain (IRD, rear diff, drive shafts)?
The V6 IRD does have different gear ratios, and looks different as far as the casings are concerned. There was a forum member on here a few years ago who claimed he fitted a V6 IRD on a smaller engine manual box to increase the gear ratio, but never posted pictures of the IRD fitted to the incorrect gearbox. I'm doubtful that a V6 IRD will fit in as the mount points look to be at different centers. So going by that logic, it's doubtful that the 1.8 IRD will fit the KV6 Jatco box.
I think it's going to one of those "try it and see" situations.

The rear diffs are all the same, and even the propshaft should be the same too.
 
I would prefer to keep 1.8 gear ratios I think.
When you say that the mounting points look different, do you mean how the IRD mounts to the transmission?
I'm not sure if the IRD only bolts to the transmission or whether it also bolts to the engine block.
 
Nodge, do you know if the TD4 IRD is like a 1.8K one or a V6 one?
I have a TD4 IRD lying in my back garden so when I go to get this V6 Jatco I could take the TD4 IRD with me and see if it mounts on or not.
But of course just because a TD4 IRD will mount to the Jatco does that mean that a K series one will?
 
I understood the TD4 and 1.8 IRDs were the same. The V6 has different ratios but as to whether it is the same externally I cannot say. Interestingly Bell Engineering only list one IRD. Why not give them a ring, they would know for sure.
 
I understood the TD4 and 1.8 IRDs were the same. The V6 has different ratios but as to whether it is the same externally I cannot say. Interestingly Bell Engineering only list one IRD. Why not give them a ring, they would know for sure.
That's correct Andy. All 4 cylinder IRDs are interchangeable, be them from a diesel or petrol engine, although the earliest IRD had a slightly different ratio for the rear output, which "may" have contributed to many early failures. Any 4 cylinder IRD after the MY2001 redesign will have the later ratios.
The KV6 IRD was different, with different gear ratios and different bearings, which I believe will take more torque than the 4 cylinder IRD.
 
another question.
The ABS controller can see both engine revs and wheel speed.
Maybe it's the ABS controller that decides whether you are in first / reverse or some other gear?
That relationship changes with different final drive (IRD) ratios so I wonder if the ABS controller is calibrated differently for this?
An what happens when you fit a non standard gearbox / IRD ratio?
I think that the only consequence would be that maybe it will lock me out of hill descent because it will never accept that the car is in first gear. Probably not a big deal for SWMBO
 
or another possibility is that the auto gearbox ECU talks to the ABS controller over CANbus
I wonder what happens if you have manual ABS controller with an auto gearbox
I'm guessing that it would just ignore the gearbox ECU but maybe the gearbox ECU will give annoyed that the ABS is ignoring it
 
Sorry to gate crash your thread but since we are talking about IRD's I'd appreciate folks opinions on the necessity of cooling the IRD in my Freelander EV. (I'm in the process of plumbing the engine bay)
I was thinking that because it won't be bolted to a hot engine and be close to an even hotter exhaust it may not be necessary.
Any thoughts guys?
 

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