R51 YD25 4WD light stays on - possible fix.

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TSki7003
Posts: 3
Joined: Tue Feb 14, 2017 4:29 pm
Location: UK

R51 YD25 4WD light stays on - possible fix.

Postby TSki7003 » Wed Jun 21, 2017 6:39 am

***Picture links added at bottom of post***

Hi everyone.

I wanted to create this topic for anyone having the issue in the title, that being; you start the motor up, and either the 4WD light doesn't go out, or the light comes on after 'x' seconds/minutes and the vehicle enters 'limp mode', you can't drive, and have to turn the motor off then on again to get it back to normal.

For me I like to let oil flow through the turbo when I first start a vehicle so I sit there for a few minutes before setting off on a journey, this was when the light would appear and nothing I could do; different gear selections/moving the 4wd selector, would get it to go. I HAD to switch off the motor every time for it to go away. Now when the motor was warmed up this light didn't used to come on at all, it was from cold starts always.

If you have the above, I recommend investing in an OBD scan tool. Amazon supplied mine for around £5 and its used with a smart phone over Bluetooth to read codes and variables.

If the light is on, use your scanner to check the fault codes, and you may see one saying something like ' SCV...', SCV being Suction Control Valve. This is what was the cause of my issues. The SCV is used in the fuel system and lives in the engine bay on the UK Drivers side, and is quite accessible.

You have a choice; let a garage change it, or follow my steps and do it yourself.

I was incredibly lucky to have mine off EBay for £45 brand new (seller refunded me postage as he got it wrong too!)

Parts needed - 1. New SCV (included should be new machine bolts, and seal pack)
2. Allen keys
3. 1/4 drive ratchet
4. 1/4 socket
5. The correct size Hex to fit into the 1/4 socket and the machine bolt (these can be found as part of drill accessory kits) I think its was size 4 or 5.
6. A long flat head screwdriver (optional)
7. A hammer (optional)
8. Gloves
9. Kitchen roll
10. 10mm socket and wrench

Using the 10mm socket, take off the engine cover.

Unhook the white fluid bottle in front of the battery from its holder for access.

Place some kitchen roll down the gap toward the bottom of the oil dipstick so as to catch some fuel/bolts/seals.

Remove the bolt holding the oil dipstick bracket on for access.

There is a black fuel hose just above the SCV, its easier to remove it for access to the rear bolt on the SCV.

Remove the plug attached to the SCV, just press down on the upper face and pull.

You can now use the Allen key to remove the two bolts holding the SCV on. If you find that there isn't enough purchase on the bolts, try using the 1/4 socket with a hex bit inserted, or a combination of what ever you have got. I found the rear bolt came out easily, but had to use a long flat head and hammer to persuade the forward bolt to move, then continued with a Allen key.

Once the bolts are removed, there might be a bit of suction holding it in place or the rubber washer, so just be careful.

Installation is reverse of above, noting to include the new seals supplied, and new machine bolts.

Once its all back together, it might take a while to start due to the fuel pipe being off etc. Just continue and it'll fire up. I left it run until the motor warmed up, then did the ECU reset mentioned elsewhere on this forum.

Success as no 4WD light has come back, and its been installed for a week!!

Previous to this I installed new relays for the 4WD system, which didn't fix, so have some to sell if anyone is interested haha.

Any questions just ask!

https://ibb.co/mu2Q05
https://ibb.co/dvur7k
https://ibb.co/fkAaYQ

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