Engine light not displaying

[mr299ron]

I'm trying to see if there are any fault codes read through the diagnostics port. I'm pretty sure I've bridged the connections together right (e1 and te1) but when I turn the ignition on the engine management light doesn't come on.

Now, is this supposed to come on when the car's ignition is on anyway? Are all lights supposed to?

So, I took the dash apart and found the bulbs on the back of the cluster. They looked okay initially, so I thought I would test by replacing a bulb I knew that worked into where the EML is. Still nothing. I also noticed that my handbrake light was out (yes the handbrake was on) so I put a working bulb in that slot and straight away the light came on.

So these are my main questions:

1. So, does the EML come on with ignition? Are all lights supposed to?

2. The EML light doesn't come on, even with a known working bulb in place and the light hasn't been taped up. Any suggestions?

3. Am I being a knob and doing something wrong

99ron

[markstevieandmads]

Seeing you have a rev 2 turbo I would check the ECU for exploded capacitors.
Very common problem.and covered a million times on here.

If you search through my threads it shows how to test the wiring from ECU to engine management light too. I had exact same problems. Turned out it was my AFM shorting internally. But as your car is running then I'd be looking elsewhere first.

[bobhatton]

I'm trying to see if there are any fault codes read through the diagnostics port. I'm pretty sure I've bridged the connections together right (e1 and te1) but when I turn the ignition on the engine management light doesn't come on.

Now, is this supposed to come on when the car's ignition is on anyway? Are all lights supposed to?

So, I took the dash apart and found the bulbs on the back of the cluster. They looked okay initially, so I thought I would test by replacing a bulb I knew that worked into where the EML is. Still nothing. I also noticed that my handbrake light was out (yes the handbrake was on) so I put a working bulb in that slot and straight away the light came on.

So these are my main questions:

1. So, does the EML come on with ignition? Are all lights supposed to?

2. The EML light doesn't come on, even with a known working bulb in place and the light hasn't been taped up. Any suggestions?

3. Am I being a knob and doing something wrong

99ron

Yes all lights come on with the ignition on.

Sounds like you have an ECU problem, try another known working ecu

[Pauln]

All the warning lights for all options available on your car should initially come on when you turn the ignition on. From memory, the power steering light goes off after a few seconds once the systems up to pressure, always assuming it's working OK.

If you have an immobilizer fitted, the EML lamp won't come on until you switch off the immobilizer. That's caught me out a couple of times when I've been trying to diagnose faults as most alarms will immobilize the car after a short period of time if the ignition is switched on but the car isn't started.

If it's not the immobilizer, and you know you have a working lamp, you could check the back of the cluster to make sure the bulb is a good fit in the holder and the holder is making a good contact with the tracks and that all the plugs are pushed in OK. You could also check for any signs of damage to the tracks etc.

If all else fails, it could be leaking capacitors in your ECU. This seems to be a common fault on older models. I had similar issues with my Tubby, but in my case the EML lamp started fading in and out before it died all together. When I opened up the ECU I found two capacitors had leaked and badly damaged the tracks. One of the two 10mf capacitors that seem to be most prone to this is in the vicinity of the EML circuit. If it is the ECU and the damage isn't too great you can simply repair the track and replace the capacitors.

But hopefully it's just the immobilizer clicked in.

edit: Bob beat me to it, must learn to type faster

Paul

[mr299ron]

Thanks for the replies guys

The car does have an immobilizer, but it's currently not in use. i.e it doesn't work. I'll try unplugging it and seeing it that does the trick.

99ron

[jimGTS]

You need to make sure the connection is good.
A thick long paper clip is best to use, something you can shove right down in there.

The eml will not start flashing for a couple of seconds usually.

If never heard of anyone not being able to read codes, so you just need to get the connection right.

[Pauln]

Thanks for the replies guys

The car does have an immobilizer, but it's currently not in use. i.e it doesn't work. I'll try unplugging it and seeing it that does the trick.

99ron

If the immobilizer has been disconnected and you are still able to drive the car, that's unlikely to be the issue.

Unless I've misunderstood, it doesn't sound as though this is just a case of not being able to read out any error codes as even in normally use (ie without the diagnostics port bridged) the eml light still doesn't come on when you turn to ACC.

If that's the case, I'm afraid it really does sound like an ECU fault.

[mr299ron]

Okay Jim, I'll try something thicker, although I'm sure the connection was pretty solid.

Paul, the EML doesn't come on at all bud. I thought it would at least appear with all of the other lights when the ignition comes on.

[Pauln]

Okay Jim, I'll try something thicker, although I'm sure the connection was pretty solid.

Paul, the EML doesn't come on at all bud. I thought it would at least appear with all of the other lights when the ignition comes on.

Yep the eml light should always come on when you first switch on the ignition along with all the other warning lights to show that they are all working OK. Once the engine is running the EML light should go out. It should only come on when the engine is running if there is a fault.

When you bridge the diagnostics port with a paper clip it should flash to show if a fault code has been stored or not.

So if the EML light doesn't come on at all with known working bulb, there is something wrong with the actual circuit.

If the paper clip isn't making contact in the diagnostics port, that won't stop the EML light from not coming on when you turn on the ignition - it just won't flash to tell you if there's a fault code stored.

If there's a fault in the EML circuit in the ECU, that will stop the warning light coming on when you turn on the ignition. That's exactly what happened to me earlier this year. Whilst there could be a fault elsewhere in the EML circuit, I'm afraid my moneys on the ECU.

Paul

[mr299ron]

Okay, thanks Paul, really appreciated.

It's not an issue at the moment, but I'll get my saving hat on for a new ECU

[Pauln]

It really is worth whipping the cover off the ECU just to see if there are any signs of leaking capacitors on either of the PCBs as you might be able to repair the board before the damage gets any worse.

Unfortunately the gunk that can start to leak out of the capacitors can easily start to spread and eat into more tracks, so if this is the problem it's best to catch it early, as I found out the hard way.

Unfortunately I believe the ECU on the rev 2 is only used on the rev 2, so tracking down a good rev 2 ECU can take while. Rev 3 + ECUs and even Rev 1 ECUs seem to come up much more often.

Good luck.

Paul

[mr299ron]

Thanks so much for the heads up Paul.

I'll keep an eye out, if not I'll just install a decent aftermarket ECU, such as the Apexi commander

[tiff_lee]

Not sure what the pinout is for the Rev2 ECU but on the Rev3 the EML is supplied from the ignition switch via a 10A fuse to Pin W on the ECU and grounded via Pin E1.

Short of opening the ECU up an easy check would be (providing you know the correct pinout) is turn ignition on and check 12V ish at Pin W and check the ground is good at Pin E1 (this example based on Rev3). If both pins test ok then as the guys said ECU problem.

It could be a damaged wire from the EML to ECU or a bad ground..... but how likely is that given the history of capacitors failures, not likely.

[mr2magic]

Just a word to the wise......

when testing a failed ecu, never ever ever ever (did i say ever!?) place another ecu in the car with the possibly failed ecu!! If you have a wiring problem you may fry the new one too - your friend/wife/brother/uncle.... will not be happy!

The better way is to remove the defect ecu and try it on another car.