Fault 12 Hilux Surf

[StevenB]

I have a 1992 2.4 diesel Hilux Surf that is showing a 'Fault 12' on the onboard computer. The vehicle starts up and ticks over perfectly but will not increase its speed.

Its been to the diagnostic centres of 2 Toyota / Japanese car dealers and neither have been able to clearly identify the problem past acknowledging the Fault 12. I have paid both of these considerable sums of money and yet they have not helped.

Can anyone help please, as its a great vehicle which I want to keep?

Regards

Steven

[clean_me]

This is part of a post from this site back in 2005:

"code 12 is the pump timer or it's control, there are some electrical tests that can be carried out on the pump electrics; but it can be mechanical,
(resistance checks to test circuits to each sensor/switch/plunger etc)
the crankshaft position sensor can also give rise to code 12"

...don't know if any of that is right, but it might help.

This seems pretty helpful, too:

http://www.troublecodes.net/Toyota/

This says it could be an RPM signal - that might fit what you're experiencing, if your engine won't rev...

Might help?

Cheers.

[Albannach]

I have a 1992 2.4 diesel Hilux Surf that is showing a 'Fault 12' on the onboard computer. The vehicle starts up and ticks over perfectly but will not increase its speed.

Its been to the diagnostic centres of 2 Toyota / Japanese car dealers and neither have been able to clearly identify the problem past acknowledging the Fault 12. I have paid both of these considerable sums of money and yet they have not helped.

Can anyone help please, as its a great vehicle which I want to keep?

Regards

Steven

An introduction would have been nice.

Have you tried resetting the ecu? If the truck runs OK, don't worry about it.

[NiftyNev]

I have paid both of these considerable sums of money and yet they have not helped.

Ask for the money back and send it to me.

12 is the Timer Control Valve. It could be faulty or it could be a timing problem. Most of the time this fault code is a result of a worn timing belt that has skipped a tooth or more on the pump. Solution is to replace the timing belt before disaster strikes and you need a new engine. Have you any idea when the timing belt was last done?

Nev

[StevenB]

Many thanks Nev, really appreciate you taking the time to reply.

The Timing Belt was brand new and changed just as a matter of course when the head was changed. The problems then occurred around 7 months later, after the vehicle had bee running perfectly.

I had the engine timing checked when the problem first occurred and the result was timing was perfect.

I would be happy to pay you to get it fixed.

Kind regards

Ask for the money back and send it to me.

12 is the Timer Control Valve. It could be faulty or it could be a timing problem. Most of the time this fault code is a result of a worn timing belt that has skipped a tooth or more on the pump. Solution is to replace the timing belt before disaster strikes and you need a new engine. Have you any idea when the timing belt was last done?

Nev

[StevenB]

Many thanks, great help, will check those areas.

Kind regards

This is part of a post from this site back in 2005:

"code 12 is the pump timer or it's control, there are some electrical tests that can be carried out on the pump electrics; but it can be mechanical,
(resistance checks to test circuits to each sensor/switch/plunger etc)
the crankshaft position sensor can also give rise to code 12"

...don't know if any of that is right, but it might help.

This seems pretty helpful, too:

http://www.troublecodes.net/Toyota/

This says it could be an RPM signal - that might fit what you're experiencing, if your engine won't rev...

Might help?

Cheers.

[Albannach]

Is my post invisible? Have you checked the TPS? When I changed mine, it cured fault 11 & 12.

Is Essex near Australia?

[NiftyNev]

Is my post invisible? Have you checked the TPS? When I changed mine, it cured fault 11 & 12.

Is Essex near Australia?

Yeah, check the TPS. Specs are available on the Aussie site. TPS can cause a fault code 11. Never heard of it causing a 12 but worth checking anyway.

Don't tell him I'm in Australia. I wouldn't mind a free trip to the UK.

Nev