'02 GV 2.5 CRD limp-home mode
 

Hi all,
New here, so apologies if this is an old, tired question.
I have a 2002 Grand Voyager, 2.5 16v diesel and five-speed.
It keeps dropping into limp-home mode, with no obvious cause. It usually happens at cruising speeds, 40-70mph, though it has happened at town speeds too. It doesn't matter if it's hot, cold, wet, dry, uphill, downhill or anything else. If you turn the ignition off, wait a few seconds and switch back on again, it's fine. I can now do this on the fly in the fast lane...
I've got an Actron code reader, and I've had friendly mechanics put their Snap On code readers on it, but ALL say the same thing - "Yes, the MIL light is on; no there are no codes or problems stored."
I came on here and learned the "key dance" and it came up with the following:
P1130
P2120
P1511
P0520
P0500
P0620
Now what the hell does all that mean? The thing has well in excess of 250,000 miles and not a straight panel on it, so I'm loath to throw any money at it, but apart from this limp-home mode issue it just doesn't want to quit...!

As you don't want to throw money at it, an easy and cheap check is to replace the battery with a known good one (borrow one if you don't have one to hand) and then see what happens. It will either cure or not as the case may be. Sounds ridiculous as a cause, but try it -- there are all sorts of complex electronic reasons the battery may be the culprit. Be ABSOLUTELY sure the fresh battery is connected with the right polarity.

Leedsman.

p1130 - fuel rail pressure error
P2120 - accelerator pedal cct1
p1511 - battery voltage too high
p0520 - oil pressure signal implausible
p0500 - speed sensor too high
p0620 - alternator voltage too high

The key dance doesn't tell you everything and doesn't tell you what is active and what is a stored code. Where about are you?.

Regards
Richard

All your limp home is likened to P1130 as in pressure in rail on low side.
But you seem to have two problems there, other is like Leedsman says Battery output voltage. Its maybe even an IPM issue on corroded connectors.
Got to start somewhere, so try a good battery (if solved buy new). Check Alternator output and gives a reading on that, clue maybe there.

Thanks for all the input, folks. I've been away in it over the weekend, only 50 miles away, and it did the drop-into-limp-mode trick four times on the way home.
I'm not sure what the battery issue could be, as it's only about 18 months old and has never gone flat or failed to start.
I'm in south Staffordshire, Richard.
Dave

Hmm, that's a bit of a distance from me as I'm in Cambridgeshire. I can scan and clear codes for you.
Did it go into limp mode when accelerating hard or under normal conditions?

Regards
Richard

It happens under all sorts of conditions, usually cruising at a constant speed.

Then I would start looking at the accelerator circuits. Most likely to be dodgy wiring from the pedal unit to the ECU...bit of a bugger to find without proper diagnostics though.
You need to get all the codes cleared and then after it happens use the keydance to see what new code has popped up and confirm it is the accelerator before investing any time or money into diagnosis

Regards
Richard

How does one get all the codes cleared? I have my Actron hand-held code-reader which can "clear codes" but it doesn't seem to do the trick. All it does is turn off the MIL which then just comes back on again moments later...

I'm coming up with EGR sticking if going into limp mode when cruising.