Engine light not coming on

[c150student]

Hi all,

I've been doing a bit of research, and found nothing conclusive.

I recently bought a 1999 1.9tdi 110 Toledo. It runs fine, but I noticed that when I turn on the ignition, the engine light doesn't illuminate at all. This is the light in the middle row on the far right (5x3 grid). I found someone with a similar issue with a 150bhp Leon tdi, and they had the light replaced and it was always on i.e. the seller was hiding something.

However, in the manual the Diagnostics light is given an asterisk, meaning 'not available on all models'. I also watched a few videos of Toledos starting, and many of them don't have the engine light come on when the ignition is switched on. An example is this one: youtube.com/watch?v=BUo5kLHFv6Y

There's several others too, and I can't imagine they've all had the bulb blanked off. Nonetheless, is there any way I can check the car isn't hiding a fault?

 

[Slimy]

The easiest way will be to plug an OBDII tool into the diagnostic port and read the codes. Look in the VAGCOM section to see how to do that.

As far as I know, all mk2 Toledo's should have an engine management light, and it should light with the ignition. I don't see any reason not to have one.

 

[c150student]

Thanks for the quick reply!

I was looking at getting a bluetooth OBD2 reader anyway, so I can do that.

Still investigating myself, it seems that the petrols and PD diesels have an EML come on with the ignition, but the non-PD engines don't seem to...

EDIT: Seems I may have made this topic a bit prematurely, as I found this about a Skoda Octavia: honestjohn.co.uk/forum/post/index.htm?t=66347

Strange, seeing as if I shine a torch onto the dashboard I can see that the engine management light is present (you can see the stencil, for lack of a better word) but I guess either a) I'm wrong! or b) its a dashboard common to all Toledos but the non-pd tdis use the glow plug light instead.

 

[Seatmann]

Your coil light will usually flash for a few of the faults, we still get a light, just not the same as the newer cars. Coil light for brake lights, switch, faulty #3 lift sensor etc, we've got the abs light for the braking system and the air bag light for the air bags. I don't know how they decide which faults should throw the light up but as for the rest just read them as said. I use an autel vag405 for most stuff and use the vagcom for timing etc.

 

[c150student]

So you don't have a proper engine management light either? Like a picture of an engine with a lightning bolt through it?

I have a Vauxhall Astra that's for sale, and its EML is permanently on. My mate suggested removing the bulb, and I said no, but checked the 'new' Toledo and saw that it wasn't lighting up at all, then panicked!

 

[Seatmann]

No none of the older cars did I don't think, I get the immo, airbag, coil, battery etc but I don't have that one.


Your astra maybe needs a lambda sensor.

 

[c150student]

Cheers matey, put my mind at ease!

The EML in the Astra is coming on because of the EGR valve, even though thats been replaced. What it really needs is... selling!

 

[Muttley]

Seatmann, do you mean you don't have the indicator at all, or that it's there but it doesn't light up during the pre-start check?

As far as I know, the "excess of pollution" i.e. the ecu warning light, should always come on during that period between turning the car on and starting the engine. Every Toledo with an ECU has that light, but I think there is an SD model in the range that doesn't.

Mine doesn't come on, and I suspect that a previous owner has masked the back of the indicator panel in the dash with a piece of card. I haven't got up the courage to disconnect the dash and check it out though. Dealer checks show no fault codes other than EGR, which I've disabled.

 

[c150student]

Muttley, from what I've seen, every Toledo has that light on the dashboard, but an 'input' to it is only provided on the petrols and PD diesels. I gather that the glowplug light works in the same manner as the engine light on the other TDIs. There's no point rearranging the dashboard just for those cars though, so the place for the light remains but it never lights up... in theory!

I'm guessing you have a 1.9 tdi 110?

 

[Seatmann]

Yeh I'm sure that light is for cars with dpf's etc that have those lambda things, I don't know if they're lambdas in diesels or what they call them but I certainly don't have the light and I only have the one fault which is for the fuel temp, (wiring issue) my car also runs really sweet with no hiccups whatsoever and starts good everytime, I get no smoke to speak of either or any other visible problem.

 

[Muttley]

Lets check that we're all talking about the same picture.

The light I'm talking about is middle row rightmost, no.22. That's the one I'd expect all cars with an ECU to have, to indicate a problem logged by the ECU requiring a visit to the dealer, or a session with the spanners. On my TDI 110 (ASV engine) I don't recall that this has ever lit up, which is embarrassing as I should have checked it when I bought the car.

The glow plug light (middle row leftmost, position 29, has a coil symbol on it for diesels) works as expected when starting the car. The manual does also say

"Note
If while driving a fault occurs in the diesel engine management system, this is indicated by the warning lamp flashing. The engine must be checked as soon as possible by a Technical Service Centre."

Which is the functionality normally ascribed to the "Excess of pollution" light, also known as the "Check Engine Light".

It's no good, the only way to check is to get the dash off and see if there is an LED underneath that symbol.

 

[Seatmann]

Yeh that's the one we don't all have, I certainly don't and neither do a lot of the tdi's, there's nothing there, go and look but I can tell you now you wont find anything. I think they use the same clocks for lots of cars because the speedo can be adjusted with vagcom/vcds and they'll just have whatever your car needs. We don't have the apropriate immissions system on out cars to make use of that light. Most of ours are all vacuum asv and egr and there's no lambda type thing but newer cars have all of these things.
Unplug your tps and the glow plug light will flash, unplug your #3 injector and it'll flash, unplug the brake light switch or remove the bulbs and it'll flash etc. Seriously bud I wouldn't fret over that light because our cars just don't use it in tdi form but would if they were petrol.

 

[Muttley]

Diesels don't have lambda probes because the exhaust is always oxygen-rich (except at full power) so you can't run a three-way catalyst and there is no need to monitor the exhaust oxygen content to ensure it stays within the limits for a three-way catalyst to work. But the system is monitored by the ECU which adjusts fuelling (in petrol cars) to keep the exhaust oxygen content correct. There's no direct connection between the lambda probes and the "excess of pollution" indicator.

Hmm. Anybody with an ASV engine ever seen indicator 22 light up?

 

[Seatmann]

Diesels don't have lambda probes because the exhaust is always oxygen-rich (except at full power) so you can't run a three-way catalyst and there is no need to monitor the exhaust oxygen content to ensure it stays within the limits for a three-way catalyst to work. But the system is monitored by the ECU which adjusts fuelling (in petrol cars) to keep the exhaust oxygen content correct. There's no direct connection between the lambda probes and the "excess of pollution" indicator.

Hmm. Anybody with an ASV engine ever seen indicator 22 light up?

Yeh I know about that on the petrol cars but the newer vags have something down there too, especially in the states. There's a number of people on the tdiclub site moaning about it and also it comes on in newer cars with the egr valve which as you'll know is now electronic rather than vacuum like ours.

You should try MJ, he's bound to know more, I'll ask dbw in the states too because he's a fairly clued up guy. The only problem is he might give me to much info and melt my brain

 

[c150student]

Yup, block 22 is the light I'm talking about too. I can see that the silhouette for it is there, but the light never comes on. As said, the glow plug light does the same job on these diesels.

In the handbook, it describes that block 22 as the diagnostics light, and says its not applicable to all models. I've watched several videos of people starting their Toledos in the cold, and of about 5 or so tdi 110s, none of them have light 22 come on when the ignition is switched on.