no glow plug light on dash

[michaelburrows]

it was minus 3 this morning.  i went to start my 62 plate focus 2.0 tdci. strangely today there was no indicator on the dash.  started it anyway no probs.   any idea as to why.   also my xenon headlamps have decided to condense a bit inside unit. so id like to know how i can cure it if poss.  thankyou

[Typhoonf2]

There was no glow plug light on mine this morning either (1.6 tdci ) at minus 4 but it did flash up about hill start assist not being available for a split second.

[erictcleric]

It's a bit random. The other day mine insisted on going through the pre-heat process when it was about 3C; today it was colder and started straight away. 

For the headlights a small amount of misting in cold weather isn't a problem. Putting the lights on should heat up the air inside and dry them out. There are also some rubber breather pipes on the back of the headlights; check they're not blocked as they allow the damp air to escape. 

If the misting becomes bad then it may be the seal around the light unit that's gone. Either that will need resealing (which is difficult and not always successful) or a new light unit (expensive). 

I once had it so bad on one car that one of the headlights was half full of water. That probably counts as a replacement light situation 🙂

[michaelburrows]

thanks guys.  my glow plug indication has been working all over the colder weather weve been having.  today it hasnt shown.  and its still not.  very peculiar.   i shall check the headlamps for some sort of breather bung also.  

[TomsFocus]

I wonder if the PCM doesn't want to waste battery voltage on long preheating and powering all the modules with just ignition on, risking it not being able to crank in cold temps?

The glowplugs will still be operating though, they aren't actually connected to the light at all.  They stay on for a few minutes after start up as well.

[michaelburrows]

thanks for that tomsfocus.   i wondered if the light in dash had failed somehow.  thought id try going into hidden menu.  i.e  holding ok button down on left side of steeri gwheel and then pushing start button untill test showed on centre screen.  but mine dost do what you tube shows     cant get guage sweep or get it to show all leds.  that i assumed would show all lights at same time.  but mine dosnt do either of these functions.   i do t think it be anythibg to do with low battery as only came back from yorkshire last night  so should have fairly gud charge. 

[billyboy]

It took me a long time to see my glow plug light It only flashes briefly for less than a second, I have to watch the light as I switch the ignition on.

[michaelburrows]

mine had been fairly visual.  i used to look for it. in cold weather unless the light was extinguished you could not activate the starter motor. you would press start button and nothing  then when extinguished it would start on its own.   so i really dont know whats gone on.    its another cold night.   ill look out for it again in the morni g

[TomsFocus]

The light is timed, so for example it might be 0.5 seconds at 5c...and 1 second at 2c.  (Don't know exact figures). But the plugs are on for a lot longer than that, they pulse on and off every few seconds as well 

The engine won't attempt to start until the light has gone out on Euro5 cars, but that's only for emmisions reasons.  It would start absolutely fine if the the PCM wasn't restricting the starter at that point.  Would just be a little smokey...

The dash test should work on the MK3 but tbh it'll be cold all week so you should notice the light next time you go out anyway 

[erictcleric]

If I don't use the car for a couple of days in the cold weather then the glow plug light seems to stay on a bit longer, and occasionally the engine start is delayed. If it gets used regularly then the light barely comes on. This evening it was 1C and I didn't even see it come on. 

[michaelburrows]

well. last night i did the hidden menu test.  lit up all the dash lights   guage sweep etc.   the glow plug symbol def lit up then so obviously no prob there.  but turned on ign this morning. still no glow lamp symbol on dash.   but car still started just fine.    finding this very wierd.   it has up untill yesterday been lighting up as and when required. 

[TomsFocus]

13 hours ago, erictcleric said:

If I don't use the car for a couple of days in the cold weather then the glow plug light seems to stay on a bit longer, and occasionally the engine start is delayed. If it gets used regularly then the light barely comes on. This evening it was 1C and I didn't even see it come on. 

Engine bays are so well insulated nowadays that they will hold heat a bit above ambient for several hours.  The plugs use the intake air temp sensor under the bonnet, not the ambient temp sensor in the mirror, so it's totally possible that it's still got some residual heat from last night when you use it the next morning.  

[michaelburrows]

strangely this evening the glow ug light reappeared. issue solved.     just the slightly steaming up headlamps to deal with.  so any ideas tom??

[TomsFocus]

13 hours ago, michaelburrows said:

just the slightly steaming up headlamps to deal with.  so any ideas tom??

Only thing I can suggest is removing the rubber bulb caps when you go on a long drive on a dry day with the lights on to warm up and air out the light clusters.  You'll need to refit the caps at the end of the drive while they're still full of warm, dry air though, otherwise you'll just end up with more damp in there.

You could also put a silica gel bag from a shoe box in each light cluster to keep them dry. 

 

[michaelburrows]

thanks tom.  il have a look for the bulbs.