P0670 Glow Plug Controller
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From: Allentown, PA
'08 GL 320 CDI
P0670 Glow Plug Controller
Last evening I got a P0670 code and my "research" 
on this site shows it to be the controller. Just a couple "wondering" questions...
1) Some of the posts mentioned that when it fails, it defaults to max glow time. Others say that it fails in an "on all the time" state and will kill a battery overnight. It started fine this morning.
2) Some of the posts mentioned having to replace it from underneath the vehicle, but... am I correct that I see it on the top of the engine and it's a pretty straight forward R&R?
I was able to clear the P0670 code with my code reader last night, but the check engine light still stays on. The P0670 has not come back on yet, but my code reader still shows a weird looking "UF333" code, but I suspect that it is trying to read something that it is not capable of and likely needs STAR (or equivalent) to fully read/clear?
on this site shows it to be the controller. Just a couple "wondering" questions...1) Some of the posts mentioned that when it fails, it defaults to max glow time. Others say that it fails in an "on all the time" state and will kill a battery overnight. It started fine this morning.
2) Some of the posts mentioned having to replace it from underneath the vehicle, but... am I correct that I see it on the top of the engine and it's a pretty straight forward R&R?
I was able to clear the P0670 code with my code reader last night, but the check engine light still stays on. The P0670 has not come back on yet, but my code reader still shows a weird looking "UF333" code, but I suspect that it is trying to read something that it is not capable of and likely needs STAR (or equivalent) to fully read/clear?
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As far as you am concerned those are consumables. They all go at some point. Replacement is straightforward- it is accessed from top of engine front left. A few screws and it comes off. Make sure you get the updated part as they fail far less often.
They don't drain battery and they don't default to max time when broken. Only clue is harder start when weather is cold. Sometimes they throw no codes whatsoever. Sometimes they keep the glow plug light on dash for a minute after start. Sometimes they turn check engine light on.
Good luck
They don't drain battery and they don't default to max time when broken. Only clue is harder start when weather is cold. Sometimes they throw no codes whatsoever. Sometimes they keep the glow plug light on dash for a minute after start. Sometimes they turn check engine light on.
Good luck
Last edited by alx; Jan 28, 2017 at 12:56 PM.
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MBWorld Fanatic!
Joined: May 2015
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From: Allentown, PA
'08 GL 320 CDI
Perfect, that clears things up. Thank you!
Since it started well this morning (about 32*F), is it safe to assume that the code came on due to either a "glitch", or that it's just on it's last legs?
EDIT: Oh, I've seen pictures of a grey-colored controller. Is that the updated part?
Since it started well this morning (about 32*F), is it safe to assume that the code came on due to either a "glitch", or that it's just on it's last legs?
EDIT: Oh, I've seen pictures of a grey-colored controller. Is that the updated part?
Last edited by DennisG01; Jan 28, 2017 at 02:36 PM.
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e320
your truck is having a bad month!
but that is just the way it goes sometimes
i had to do the glow plug controller about a month ago, got a cel and used my cheap carsoft scanner - it did not show any codes until i went in each area and checked, was weird but i found the glow plug controller code along with a couple of others
did the glow plug controller and cleared the codes and all good
happened to be in flagstaff when i got this code- maybe the colder weather triggered it- anyway it started fine at 30 degrees the next morning even with the controller weak or whatever
but that is just the way it goes sometimes
i had to do the glow plug controller about a month ago, got a cel and used my cheap carsoft scanner - it did not show any codes until i went in each area and checked, was weird but i found the glow plug controller code along with a couple of others
did the glow plug controller and cleared the codes and all good
happened to be in flagstaff when i got this code- maybe the colder weather triggered it- anyway it started fine at 30 degrees the next morning even with the controller weak or whatever
Thread Starter
MBWorld Fanatic!
Joined: May 2015
Posts: 1,932
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From: Allentown, PA
'08 GL 320 CDI
I know, right! But there's that old saying that things happen in three... So far I've got two things 
Oh well, it is what it is.
This morning the the front end was at normal height. I suppose once I see it happening a little more regularly I can at least check the lines and such to see if the leak is somewhere else. I'm thinking, though, that if it was a line it would happen much quicker and not "fix" itself, at least temporarily.
Oh well, it is what it is. This morning the the front end was at normal height. I suppose once I see it happening a little more regularly I can at least check the lines and such to see if the leak is somewhere else. I'm thinking, though, that if it was a line it would happen much quicker and not "fix" itself, at least temporarily.
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Thread Starter
MBWorld Fanatic!
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From: Allentown, PA
'08 GL 320 CDI
I'm hoping, too!
I'm not sure how old they are - I've had the vehicle for a year and half, but don't know the history of the air struts before me. Is there a way to tell if they're Arnott? Although, IF they are Arnott, would Arnott extend their warranty to a second owner? Most companies don't do that, but I have not checked, either.
EDIT: Nevermind about "is there a way to tell"... Obviously I can just take a look at them!
I'm not sure how old they are - I've had the vehicle for a year and half, but don't know the history of the air struts before me. Is there a way to tell if they're Arnott? Although, IF they are Arnott, would Arnott extend their warranty to a second owner? Most companies don't do that, but I have not checked, either.
EDIT: Nevermind about "is there a way to tell"... Obviously I can just take a look at them!
Last edited by DennisG01; Jan 29, 2017 at 08:13 PM.
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