Technical Service light and glow plug light question

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Technical Service light and glow plug light question

nigelvan

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I have bought a 2007 3.0L Citroen Jumper a while back to convert into a camper van. On the instrument panel, I noticed 2 things:

When starting when the weather is quite cold, the glow plug light blinks for about 30 sec, then goes out.
Does this mean that the glow plugs have done their job and it's ok to start, or does it signal an issue? I have been able to start the engine in about -5 C this winter without any issues... The light never comes on after starting the engine. It's just that the manual I found didn't give me a clear answer.

Secondly the service light (the wrench symbol) is on for quite some time, I have serviced the vehicle myself (replaced all filters, oil change...). Can I reset the light somehow?

For the record I have no MIL nor any P-codes thrown since I replaced the throttle body.
 
Being a Citroen, it is probably different to Fiat. With Fiat, the service schedule has to be reset when servicing.
Glowplug seems to be OK if starting at those temps. Probably just a Citroen anomaly.

Ian.
 
From the manual for the (similar) Peugeot Boxer of that vintage:

"Diesel pre-heating warning light
Turn the key to the MAR position.
In cold weather, wait for this
warning light to switch off then
operate the starter (AVV position)
until the engine starts.
If the temperature is high enough, the
warning light comes on for less than one
second, you can start without waiting."


As for the wrench symbol, I suspect the Citroen may be like the Fiat. If so, (and I don't guarantee it) the reset procedure needs dealer-level software intervention, but running with it un-reset will result in it clearing itself with something like an extra 1000-1500 km under the belt.
 
Thanks for the answers so far. The Jumper/Boxer/Ducato versions seem to be identical so far, except for the logo slapped on :). This Fiat forum is so active and helpful I'll probably stick a Fiat logo on the Jumper anyway ;-)
 
The Peugeot and Citroen are very similar, sharing the great majority of components.

Most of the Fiats have significantly different engines, though - so your Citroen query isn't easily answered by reference to the Ducato.

The instructions in the Peugeot handbook, though, are probably relevant to the Citroen, as they share engines (and I had easy access to the online manual :D).
 
Hi nigelvan

The handbooks are vague about the glowplug light.


If the weather is cold, the glow plug light stays on steadily for longer than normal (though still maybe only a few seconds), to tell the driver to wait briefly before cranking and allow the plugs to get properly hot. Note that after the steady light has gone out and you start the engine, the glow plugs actually stay energised for anything up to about 15 seconds depending on engine temperature. This extra time is nothing to do with starting but reduces emissions. So the light isn't directly associated with the plug energisation.

With Fiat/Iveco engines, a FLASHING glowplug light normally indicates a fault with the glowplug system which has been detected by the glowplug controller, for example one or more plugs are drawing too much current (internal short) or too little current (burnt out and gone high resistance or open circuit).


With one open circuit glowplug and three glowplugs still working, you may not notice any difficulty with starting unless its really cold. The cylinder with the faulty plug may briefly cause rough running till it catches up. On the other hand if you get a shorted glowplug the controller will rapidly cut power as a protective measure, and the other three glowplugs will only come on for a fraction of a second. Effectively you have lost all glowplug function and this will make starting difficult if its cold.

If the weather warms up to above a certain temperature (+10 deg C from memory) the glowplugs aren't used at all unless you have a later van with tighter emissions control. After something like 6 starts in mild weather with no fault detected (because the system isn't being used) the flashing warning is cancelled by the software and will no longer appear, but a fault code P0683 will remain stored. Clearly, if there is a genuine glowplug fault then as soon as temperatures go below +10C your friendly flashing light will return !
 
Hi Anthony489, thanks for helping me out again!
I suppose I can locate the controller and measure resistance to check which one(s) is bad.
Reading a bit around it seems these glow plugs often seize into their place and it's a specialist job to replace them.
 
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Hi Anthony489, thanks for helping me out again!
I suppose I can locate the controller and measure resistance to check which one(s) is bad.
Reading a bit around it seems these glow plugs often seize into their place and it's a specialist job to replace them.

Its worthwhile checking they are actually getting power ..

The flashing light is often a helpfully vague 'glow system error'

A blown maxi fuse can mean no power to any plug :eek:
 
Yes I'm going to start there, but I think if none of them had any power the van wouldn't start so smooth in freezing temps, right?
 
Thanks!
Will keep you guys posted. Although could be a while: There are some more pressing concerns as we are getting our camper conversion ready for a first trip to the south of Belgium.
The brake discs are in an awful condition. I'll tackle that first since no glow plugs sounds better than no brakes :-D
 
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