W211 glow plug relay... glow time

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Oct 15, 2021 | 01:40 PM
  #1  
Hi can someone help...
I have replaced glow plug relay and have same problem as before replacing it... Glow plug light goes out too quickly (1-2 second) and (hard) wont start in temp lower than -4C. I made custom wiring battery+ direct to all plugs for testing purpose. I connected a switch off course and pushed it aprox 3-4 second before cranking... and it started immediately -8C. help please.??

I have 0 voltage when glow light is on ..
Reply 0
Oct 21, 2021 | 10:24 PM
  #2  
What temperature does the car think it is? This will directly affect the time the glow plug relay allows the plugs to heat.
Even without a glow cycle, the car should start without too much trouble even when it's COLD outside - like easily down to zero F.
Reply 0
Jul 12, 2022 | 08:33 AM
  #3  
Quote: what professional mechanic diagnosed your car and indicated the relay was faulty
There was no mechanic... just scanned with obd and got fault code "glow plug output stage... Can you help?
Reply 0
Sep 2, 2022 | 05:20 AM
  #4  
Can anyone help me to diagnose this problem...?
Reply 0
Sep 2, 2022 | 05:22 AM
  #5  
Glow plug light goes out too quickly (1-2 second) and (hard) wont start in temp lower than -4C
Reply 0
Sep 2, 2022 | 11:45 AM
  #6  
You need to scan with a scanner that reads all MB codes and see what you find.

1-2 seconds is normal...both of mine do that.
Reply 0
Sep 4, 2022 | 04:20 AM
  #7  
Quote: You need to scan with a scanner that reads all MB codes and see what you find.

1-2 seconds is normal...both of mine do that.
Hi.. even its +4C or -4C or -14C.... light is on 1-2 second. I think glow plug relay doesn't get power. What controls glow plug relay?
Reply 0
Sep 4, 2022 | 10:55 AM
  #8  
Quote: You need to scan with a scanner that reads all MB codes and see what you find.

1-2 seconds is normal...both of mine do that.


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Sep 13, 2022 | 03:57 AM
  #9  
?
Reply 0
Sep 13, 2022 | 04:00 AM
  #10  
Quote: You need to scan with a scanner that reads all MB codes and see what you find.

1-2 seconds is normal...both of mine do that.
Can you Help?
Reply 0
Sep 13, 2022 | 05:19 PM
  #11  
If you suspect that there's no power, pull the relay and remove the single red, thick wire, and measure the voltage. If that checks ok, check continuity of the ground wire (brown, BN).
If there is no voltage on the red wire, you'll find the fuse from the passenger footwell (under the carpet, styrox pad and steel plate), second fuse from the left, 150A fuse.


Reply 1
Oct 2, 2022 | 08:11 AM
  #12  
Quote: If you suspect that there's no power, pull the relay and remove the single red, thick wire, and measure the voltage. If that checks ok, check continuity of the ground wire (brown, BN).
If there is no voltage on the red wire, you'll find the fuse from the passenger footwell (under the carpet, styrox pad and steel plate), second fuse from the left, 150A fuse.

There is no fuse or cable connected to this point.

Reply 0
Oct 4, 2022 | 09:53 PM
  #13  
Glow plug issues are very likely related to glow plug control module (something the scanner may not tell you). A few years ago when it failed for one of the glow plugs, I took the control module apart, repaired the solder joints that had melted, resealed the module with epoxy and it them worked for at least five years when it failed again. This time I ordered a replacement part (apparently an upgraded version) and installed it. With the right tools and some patience, its a ten minute replacement job. Shame I did not take any pictures when I did it.
Reply 0
Oct 4, 2022 | 11:51 PM
  #14  
Quote: There is no fuse or cable connected to this point.
my CDI also has a hard time starting in very cold weather, glow plug lite only come on 1 or 2 secs if that, requiring multiple start attempts, after 3 tries it usually starts, problem exhibits below 25F. I haven’t done anything to troubleshoot yet. Looking at Heguli wiring diagram, none of those colors are shown on the module you have pictured, is that even the correct module?
Reply 0
Oct 5, 2022 | 12:09 AM
  #15  
Quote: my 2006 CDI also has a hard time starting in very cold weather, glow plug lite only come on 1 or 2 secs if that, requiring multiple start attempts, after 3 tries it usually starts, problem exhibits below 25F. I haven’t done anything to troubleshoot yet. Looking at Heguli wiring diagram, none of those colors are shown on the module you have pictured, is that even the correct module?
I looked up the part on FCPEuro for a 2006 E320 CDI and pn 6481530279, doesn’t look like that.

please fix your profile with the year and class designator like “ 2005 E220 CDI” people like me, are not familiar with all the car models. Do you have a 6 cylinder vehicle?
Reply 0
Oct 5, 2022 | 02:08 AM
  #16  
Quote: There is no fuse or cable connected to this point.
Went to look if I have a picture of my fuse panel, and to my surprice I don't have fuse 69, either (2006 E280). I've looked from the interwebs to see where the fuse is, but no luck so far. Every it's said to be at #69
Reply 0
Oct 8, 2022 | 03:47 PM
  #17  
Quote: my CDI also has a hard time starting in very cold weather, glow plug lite only come on 1 or 2 secs if that, requiring multiple start attempts, after 3 tries it usually starts, problem exhibits below 25F. I haven’t done anything to troubleshoot yet. Looking at Heguli wiring diagram, none of those colors are shown on the module you have pictured, is that even the correct module?
The picture is for the fuses at passanger foot location.
The glow plug relay is located under the intake. And hard to get to.
Reply 0
Oct 8, 2022 | 03:48 PM
  #18  
Quote: If you suspect that there's no power, pull the relay and remove the single red, thick wire, and measure the voltage. If that checks ok, check continuity of the ground wire (brown, BN).
If there is no voltage on the red wire, you'll find the fuse from the passenger footwell (under the carpet, styrox pad and steel plate), second fuse from the left, 150A fuse.

What program does your wiring diagram come from? WIS is not usefull to get the whole wiring for the relay.
Reply 0
Oct 8, 2022 | 03:55 PM
  #19  
That I found with google.
Reply 1
Oct 8, 2022 | 04:01 PM
  #20  
I found this:


Reply 0
Oct 8, 2022 | 04:06 PM
  #21  
Quote: I found this:
Looks familiar, I have that saved somewhere.
Reply 1
Oct 9, 2022 | 06:49 AM
  #22  
Quote: I looked up the part on FCPEuro for a 2006 E320 CDI and pn 6481530279, doesn’t look like that.

please fix your profile with the year and class designator like “ 2005 E220 CDI” people like me, are not familiar with all the car models. Do you have a 6 cylinder vehicle?
I have 2007 model.. Vin. WDB2110081B268558
Reply 0
Oct 9, 2022 | 09:36 AM
  #23  
Hi MB_user
Have you come to any closer to an answer for the fault code 23EA?
I have changed the relay (output stage) and plugs. One pug had couple ohm resistance, the rest had Megaohm resistanse. The relay had drowned in oil. Actually a friend helped, I had to be somewhere else. And he didnt disconnect the battery and noticed there at least been incoming voltage to the relay. Thats why I was searching for a fuse - but this car doesnt have it either. MY 2008.
I still have the same fault code.
The relay is placed so idiotic so its going to be hard to even measure the pins at the connector.
So before anything - I pulled out a resistance box I have built.
Removed connector to coolant temp sensor and put in 40 kohm. Measured voltage at the glow plug connectors - and nothing. The glow light was lit for more than the 1-2 seconds at ambient temp 10C. It was lit for quite a meny seconds. So that works.
There was one other NEW fault code after my friend changed the relay and plugs (and shorted the incomming voltage connector) - 20A5-8 - probability fault, temperature sensor exhaust
Reply 0
Oct 9, 2022 | 11:44 AM
  #24  
So the fault code 20A5-008 is from a deviation between sensor B19/8 and B19/11 (temp sensor before turbo and temp sensor before dpf), the deviation should not be more than 60 C. I pulled out the Xentry and there was a test to go thrue. Engine was run at 1500 rpm for some time and the temperatures were monitored. After the test was done, the deviation was 40 C.
The 23EA is NO SIGNAL - fault code. And Xentry tells me to test resistance for the LIN buss wire between pin 12 at the relay connector and the pin 66 at ECM connector. THAT is going to be fun to do! ...or NOT!
If there is no resistance, then to check ground points. If that too is ok - then its the relay...

Guess the best way to test LIN buss is to learn how to do it with my oscilloscope. Rather than trying to connect to the relay itself.
Ill update when Iam done.
Reply 0
Oct 9, 2022 | 05:36 PM
  #25  
LIN works - cannot interpret though. Its sending signals as soon as the ignition is on ans as long ignition is on. 12V.
I have also bought one day prepriction from MB. And have the wiring. The ground is located together with other stuff, on top of the engine.
The 150 amp fuse is on cars up to 2006. After that - there is no.

Reply 0
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