Flashing hold light

[Mattwills8]

Hola Bongonauts from sunny Spain.

I’m looking for a bit of advice about my flashing hold light. From reading some topics here it seems like my next step is to plug in the diagnostic thing and read the error code, but I’m quite far from home so if anyone can identify the issue without that that’d save me a lot of trouble

I’ve got an automatic 2L petrol 2001… im currently importing it into Spain and will do a write up of the process for people here once it’s done for anyone else mad enough to try it.

So the issue…

the first time I turn on the car I see the flashing hold light, and the car over revs while I’m sat there in park, it seems to hover around 1200rpm whereas normally it idles at about 400. If I turn the engine off and on at that point it keeps doing that.

If I then put it into gear (either reverse or drive) the car does a pretty big jolt as it enters the gear, but then the revs return to a normal, and it seems to drive fine in that gear (have only tried for a v short distance). Changing gears at this point also results in a big jolt. The hold light still flashes.

Then after having put it in gear and accepted the jolt, if I turn the engine off and on again, it seems like the issue has gone away. The hold light no longer flashes, it idles at a normal number of revs, and completely smooth gear changes and drives completely normally… have done relatively long journeys like this too with no relapse.

Even if I then turn the car off and leave it for a while, it still seems to be completely normal. Then the next day the issue starts again…

Does anyone have any leads on what this might be? Seems like a really weird issue. Any advice is much appreciated!!

[g8dhe]

Can't say I have heard that sort of description before I'm afraid.
However do you have a leisure battery and swap loom fitted ? It could be that your leisure battery is not fully charged and overnight gets so low that the ECU does its reset / loss of power routine which means it needs to run and be used a little bit before it rebuilds its parameters for the vehicle, at which point the error signal (flashing light) will be reset and it will be OK again.

[Mattwills8]

Hey, thanks a lot for the reply!

I do have a leisure battery, but I’m not sure about the swap loom.

If that was the case and it was battery related, what do you think the solution would be? Would that somehow explain the over revving too? And the clunk when I put it into gear?

[g8dhe]

The ECU has a backup power supply that retains in memory the parameters for the engine, if the back up power is lost then on the next run they are rebuilt, but the hold light will flash to indicate power loss.
The backup power supply from the factory is on the unswitched supply top left of the internal fuse box. However this and up to three other circuits on the top row of the fuse box are normally switched across to the LB using the swap loom;

Willington kit fuse panel.jpg (24.17 KiB) Viewed 1575 times

So if you have a Swap Loom fitted, and the leisure battery goes flat then the settings are lost and at the next switch on the Hold light will flash, the battery may well get some charge from the next run but if the battery is dead or not holding a charge as expected then the next overnight will see the battery flat again and the cycle repeats.

[Mattwills8]

Hmm I had a look, and the fuse box looks normal (not with the extra wires that that photo has), so I’m guessing I don’t have a swap loom fitted?

Does that completely kill that theory? Or could it still be battery/ECU power related?

[g8dhe]

There are other ways for connecting the LB to the fuse panel, by making connections at the rear of the panel, but its not a common way of doing it!
You really need to check out with a meter if the LB is being used for internal Lights, Radio etc if so then its wired behind the back.
When the ECU looses all power (it has an unswitched connection for backup of values, and a power connection via Ignition switch from SB as well) then when the power is restored it flashes the error lamp without any code present (it would be lost during lack of power!) The loss of values can sometimes cause the ECU to cause the engine/gearbox to behave differently until it has been run and turned off again when it stores the values for future running.