Evening all

On Christmas Day we left my folks and the side steps on the 2007 RR were working fine. On Boxing Day morning when we were going to the in-laws I noticed that neither of the steps folded out upon unlocking the car.

I’ve removed the panels tonight to gain access to the ECU for the steps and I’ve got 12v going into the ECU, after unplugging it and plugging it back in I’m still not getting any action on the steps.

I’ve opened the plastic case and had a peek inside it and the circuit board looks clean with no signs of moisture or any visibly blown components.

Has anyone else had any similar symptoms? I’m wondering if the ECU has mysteriously failed as I can’t see any other reason for both steps failing at the same time when there’s power going to the ECU.

Thanks,
David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Mine did that a few months ago before I had to replace the battery they had switched themselves off I had to press the button on the roof with ignition off then on to switch them back on I will have a look and see if I can find what I did

Cheers Sandy.

My button illuminates with the lights being turned on but it’s not doing anything when I try to turn the steps back on either

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

If the steps are working and you want to disable them: insert the key in the dash in position 1 and hold the switch whilst turning the key to position 2, the light in the switch will flash twice to confirm the system is now off. To turn the system on repeat the procedure but the light will now flash three times to confirm the system is now on.
try this

Thanks Sandy.

Just going to plug the ECU back in so will give that a try.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Just been and had another look at the ECU in the car.

There’s definitely 12.4v going to the ECU without the engine running. I then put the meter across the feeds to each individual step and locked/unlocked the car and found that there is no power going to either step from the ECU.

It looks like the ECU is knackered unfortunately.

Probably my own fault… the wiring loom with the kit just didn’t seem to have the length in it to mount the ECU where it said it goes in the instructions. I used some heavy duty Velcro and mounted it behind the knee airbag above the drivers feet. Upon closer inspection this evening, it’s the air duct that sends hot air to the drivers feet that I attached it to so it’s probably heat that’s knackered it.

Oh well, my own fault!

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Well at least there is a reason for it and it isn't just the Range Rover fairy having a laugh

Finally managed to get an ECU for these and it’s got exactly the same symptoms.

Steps are dead…

The button on the headlining illuminates, pressing the button and holding it whilst turning the ignition on does nothing

Stumped now… got power into the ECU but it’s not doing anything with the steps.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Had another look at these yesterday:

I’m definitely getting power into the ECU, 12.4v with the car switched off, doors open and interior light on.

The switch in the headlining for the steps illuminates when the lights are switched on, however, pressing and holding it does absolutely nothing.

When opening and closing the doors there is no output from the ECU to drive either of the steps.

Changing the ECU has made no difference.

I’m fairly stumped with this one now.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

I found an hour spare this afternoon so decided I’d do a bit more digging.

When selecting ECU Info on the IID tool the Running Board ECU is listed and the car can see the ECU.

When you go to Live Values and search for “Door” then there are 2 ECU’s that appear as monitoring the door positions.

The suspension ECU just monitors the doors as a single entity as any door being open will stop the suspension from altering its height.

Click image to enlarge

Click image to enlarge

The door status is broadcast on CAN, I'm not sure if IID can interpret the data correctly or it's not receiving anything on CAN - either could be a reason for the N/A. There isn't a 'door ajar left, door ajar right' analogue input, that's for sure. I'd check the harness for twisted pairs, these will be CAN, you should get around 2.5V and -2.5V to ground from each of the pair, not less than 2.1V and not more than 3.3V depending upon network activity. I don't think I've ever seen a schematic for the sidesteps, there should be one somewhere....

Cheers Phoenix.

I think I’m going to have to start to strip the lower dash out so I can check all of the wiring for the steps as they worked fine one day and didn’t the next.

The diagram would at least help me realise where the signal comes from so I knew where to focus.

There’s definitely power getting to the module but the module for the step isn’t attempting to drive the steps when opening/closing a door.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Actually, looking at the instructions, it seems to be whatever the module that’s mounted under the fuse box is that controls the steps.

That's the radio tuner, it's only relevant as a break-in point for CAN and power

Right, I’ve done some more digging now.

I’ve dismantled the passengers side of the dash again.

There’s a heavy 12v power cable that is installed into a plug and connected directly to the fuse box.

The plug from the radio tuner is them removed and the side steps are plugged in, the radio tuner is then reconnected to a socket that’s part of the side step loom.

The side step loom is then connected to the side step ECU before a separate loom that feeds each step comes out of the ECU. There’s also a ground that’s installed in the drivers footwell.

I’m definitely getting 12v at the side step ECU but when locking/unlocking the car or opening/closing a door there’s no voltage leaving the ECU to drive either of the steps.

There’s no damage at all to the wiring loom for the steps that I can see.

Could it be the radio module have stopped giving the steps the signal they need?

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior