Glow plug light 320 CDI W210

[neilto]

Well thanks very much indeed for posting that. It looks real fiddly but I'll have a go tomorrow. I did try to break into it before I saw this using a hacksaw blade but was trying to get in at the edge rather than the top so this is helpful. Looks like he used the earth wire from twin and earth so I'll copy that. The filing looks to be the trickiest bit. If all else fails car parts 4 less have a new unit for £145. Strange that these units do not appear on Ebay at all and they all list a different looking box for Mercs but the one in the above video is the same as the one on my car for sure.

 

[neilto]

This is typical of what is listed on Ebay for the car
http://www.ebay.co.uk/itm/MERCEDES-...091053?hash=item2a58a8e8ad:g:jaMAAOSwsB9V~ZuS
It looks quite different but I think the connections are the same so it might work??

 

[vijilants]

Don't forget that there are two different looking versions of this controller.....they look totally different but fit in the same way.

From what I understand the newer version is modified.

 

[neilto]

Thanks for that - looks I'll need to order one then.
This is my unit before repair prepped.


And after (sorry about the soldering quality - its a bit tricky!


BUT it still doesn't work. In fact its a lot worse it took 4 attempts to start this morning and has always started first turn since I bought it. Orange light still on as well. I've probably fried some ICs with my hamfisted soldering!

 

[bob 6600]

Forget what ebay listings tell you, ensure it has the right part number. If ECP want £145, have you tried the dealer? Also with regards to the repair, I have seen a guide to fix the old type but not this newer type

 

[vijilants]

I am having mine replaced today with a new unit from Mercedes.....glow plug 5 keeps coming up as faulty but it is not the glowplug and wiring is OK. Looks to be the controller and not the glow plug.

 

[bob 6600]

Meter it and see if the plug is in tolerance against the others. Mercedes will replace it but they will want to do a diagnostic first (at your cost) to determine the unit is faulty. They will refund if it is

 

[neilto]

Update
Car was totally useless after the repair - it was a complete waste of time. There must have been more wrong with the unit than just the power and earth connection wires as it was very difficult to start and when it did ran with much less power than normal - like it was in limp mode and kicking out lots of white smoke even when warmed up.
Got a now unit from ebay and fitted it tonight and car started first time and no smoke. It runs fine now and no white smoke and back to normal power level. Clearly that control box does more than just heat up glow plugs in cold weather!
Anyway all is good again now. The unit was £114 and looks different from the original but works. My advice is don't bother with trying to repair it and get a new one. All fault codes clear now to.
Oh and another thing local Mercedes dealer wanted £190 for the unit and if I wanted a diagnostic running to confirm the fault it would be another 1 hour labour which would NOT be refunded if it needed a new unit - I did ask. I declined as I have my own diagnostic device (not star) which works fine.

 

[neilto]

I am having mine replaced today with a new unit from Mercedes.....glow plug 5 keeps coming up as faulty but it is not the glowplug and wiring is OK. Looks to be the controller and not the glow plug.

what are you using to determine plug 5? I don't think the diagnostics are good at determining the correct plug. if its the the controller thats gone its only giving you a clue to the problem not a specific plug as you have determined. Recommend a new controller if you have checked the plug resistance is about 1 ohm. What a ridiculous waste of time this whole glow plug saga has been. Has totally spoilt my opinion of the car. My 15 year old Toyota Land Cruiser with twice the miles has never had any of this nonsense and in fact has never shown any diagnostic faults ever! It passed it's MOT today and needed 1 drop link but I'm not bitter about that.

 

[EmilysDad]

what are you using to determine plug 5? I don't think the diagnostics are good at determining the correct plug. ...

Interestingly the Halo'd STAR said it was no 5 glowplug on mine that had failed, though the Indie did suggest that the relays do fail ...... he was right & STAR was wrong

 

[vijilants]

Interestingly the Halo'd STAR said it was no 5 glowplug on mine that had failed, though the Indie did suggest that the relays do fail ...... he was right & STAR was wrong

Exactly the same with mine. Star was showing glow plug 5 failed. Glowplug was ok but replaced as a precaution in case it was an intermittant fault.

Again Star was showing glow plug 5.

Controller replaced for the new Mercedes unit (white back) and all good.

The thing is, if there is a disconnection between glow plug and the controller (within the controller), the fault code would never point at the controller even though the controller is faulty but will always point at the glow plug.

I think the vibration created by the engine on these units is shaking the controller and causing either component failure or electrical joint failure. Don't forget that this controller is mounted near enough on the engine itself.

 

[vijilants]

My 15 year old Toyota Land Cruiser with twice the miles has never had any of this nonsense and in fact has never shown any diagnostic faults ever!

Now if it is reliability you want, yes, you buy Toyota, any day of the week

 

[alexanderfoti]

Exactly the same with mine. Star was showing glow plug 5 failed. Glowplug was ok but replaced as a precaution in case it was an intermittant fault.

Again Star was showing glow plug 5.

Controller replaced for the new Mercedes unit (white back) and all good.

The thing is, if there is a disconnection between glow plug and the controller (within the controller), the fault code would never point at the controller even though the controller is faulty but will always point at the glow plug.

I think the vibration created by the engine on these units is shaking the controller and causing either component failure or electrical joint failure. Don't forget that this controller is mounted near enough on the engine itself.

The glow plug controllers have fusible links inside them. If the plug is a dead short to ground, then the fusible link pops.

 

[vijilants]

The glow plug controllers have fusible links inside them. If the plug is a dead short to ground, then the fusible link pops.

Then whoever designed it couldn't have been thinking straight because it would appear to be ridiculous to have to sacrifice the controller for the sake of the glow plug.

It would be fine if the fuses could be replaced but as they are in a sealed unit, there is no choice but to replace the controller at £200 a pop in comparison to the glow plugs which are £20 each.

 

[bob 6600]

The last time I went to the dealers they were £120 +vat. This was within the last 12 months for the newer type for a W210

 

[virin]

Hi All,
I've had the glow plug light come on after starting and stay on. Read about it here and went through them plug by plug - one was 0.1 ohm and 5 were about 0.5 ohm. So I replaced the 0.1 ohm with a new one (which measures about 0.5 ohm). But the indicator light still comes on after starting. I had a quick look at the contol unit on the passenger side front inner guard, and it does not seem to put power to all of the plugs. This seems to be telling me the control relay is st*ffed. Is that likely? It doesn't look like this unit is able to be opened, but I'm thinking it has blown a fuse?

Your thoughts appreciated !

Cheers,
David

if you drive as such will it harm engine

 

[ChrisEdu]

Sorry to resurrect an old thread, but I'm having glow plug troubles too. W211 E320cdi V6 facelift model

I've replaced the plugs and relay, and checked the wiring harness. However, I'm still getting a fault showing on cylinder 4 - open circuit.

I checked the plug with my multimeter and got a reading of approx 1 ohm, so the plug is alright, and, as mentioned, the wiring tests intact. So, could it be the new relay, or is there anything to check?

The only other possibly relevant information is that when I had replaced the plugs, I got a faults on cylinder 4 saying short circuit to ground AND open circuit. Eventually, I removed the plug, again, to refit it incase of something not being right, and found it had warped (Beru). Now, I'm not sure if this was still in the cylinder when I installed the new relay. If it was, might it have damaged the new box?

Any ideas and advice gratefully received. Thank you.