[txdiesel]

My 335d with about 70k miles has thrown a SES light 3 times now with the code P0675 (Cylinder 5 - Glow Plug Circuit Fault) and I am considering several ways of proceeding. I wanted to see what ya'll think regarding my options here.

From my understanding from reading previous posts, it is likely related to the glow plug module itself and not the actual glow plugs (although people frequently replace the glow plugs with the module just to be safe in most circumstances). My local service adviser is telling me it's not really anything to be overly concerned about, as the module only really serves to heat the glow plug in cold situations (cold starts, severe cold weather, etc) and would likely not effect daily driving here in Central Texas due to mild weather. Here are my options:

1) Use my extended warranty ($300 deductible) and let them replace the module and maybe the glow plugs. I would have to pay for glow plug replacement as they are not covered under my extended warranty.

2) Replace the module/glow plugs myself at a cost of about $150-$350 depending on whether I chose to replace just the module or one/all glow plugs.

3) Ignore the code and watch for more severe symptoms (rough idle, cylinder misfires, etc).

Obviously, I am leaning towards #3 because of the $$$ but I want to make sure that I am not ignoring a potentially significant issue.

[kiel_dafo_kenyg_as]

If the DPF is removed I would do nothing (#3)
Some say DPF regens require proper glowplugs which somehow makes sense to me.

If you want save time and money, change the relay only ($70US)
You don't have to take off the intake manifold as it doesn't make the PITA job easier at all.

If you want to save time and money concerning future repairs change relay and all 6 plugs ($140US). Plugs come out easier when they are changed frequently and don't have time to build up a lot of carbon and corrosion in caves and threads. Intake manifold has to be taken off.

Concerning your #1 option - What would they say if you tell them to change relay and plugs by yourself if they pay for the parts?

[txdiesel]

They wouldn't say anything, the warranty is through a third party company so as long as any future issues weren't attributed to a faulty self repair, the warranty would remain intact.

[txdiesel]

Where did you find a relay for only $70?

[kiel_dafo_kenyg_as]

Just make sure you buy the GSE102 (there's a GSE101 that wont fit)
At the moment you can have it even under 70: Link1
I bought a set: Link2

[txdiesel]

Awesome, I just ordered my relay and for only $70 bucks it seems like a good place to start. If I need to replace the glow-plugs I will probably do that with a CBU clean-out as that service has yet to be performed on my car. Thanks for helping me find that cheap relay, all I could find was $140+!

[cibie]

My D threw its first CEL, SES P0675 - Cylinder 5 Glow Plug Circuit Fault. At just over 75k miles and 3 days from CPO expiration. Finally one goes my way. Local dealer, Niello, replaced the preheating control unit and associated glow plug. $50 deductive & no pressures.

[Kozlio]

i just got my P0675 and P0672 today upon ignition. so it is the glow plug control module needing to be replaced?

i am in a climate where half the year is subzero so glow plugs are used. cant imagine 2 glow plugs failing at once hence the control module common mode failure...

i won't be seeing my mechanic for another month - can i wait, or is this a critical repair i must do (ambient temp now is above zero, regens prior to this were normal, engine operating temp is 85-88C once warmed up).

thanks!

[montr]

It is likely the module as it is prone to fail. Glow plug should be fine.

[PerfectAce]

Originally Posted by Kozlio

i just got my P0675 and P0672 today upon ignition. so it is the glow plug control module needing to be replaced?

i am in a climate where half the year is subzero so glow plugs are used. cant imagine 2 glow plugs failing at once hence the control module common mode failure...

i won't be seeing my mechanic for another month - can i wait, or is this a critical repair i must do (ambient temp now is above zero, regens prior to this were normal, engine operating temp is 85-88C once warmed up).

thanks!

Should be fine. I had to wait about a week for the part to arrive and then wait a while longer until I had free time to do the repair. The car ran fine except for a rough idle for 10-12 seconds on cold starts. This was in February. Admittedly, this was also in Texas, so it was cold out, but not sub-zero.

[Kozlio]

Update: My mech is getting into his racing season so not much availability, but got myself in to replace the glow plug control module next Wednesday. The actual ses light went away for 2 days only to return to the dash today at the start of a dpf regeneration. Nothing noticeably negative to report... Driving it daily at highway speeds.

Originally Posted by Kozlio

i just got my P0675 and P0672 today upon ignition. so it is the glow plug control module needing to be replaced?

i am in a climate where half the year is subzero so glow plugs are used. cant imagine 2 glow plugs failing at once hence the control module common mode failure...

i won't be seeing my mechanic for another month - can i wait, or is this a critical repair i must do (ambient temp now is above zero, regens prior to this were normal, engine operating temp is 85-88C once warmed up).

thanks!

[Captain Buumer]

Have a story also with glow plugs on m57.

Had 1 glow plug error. (Cylinder 1), replaced glow plug and no faults for a while.

About a week later had cylinder 5 glow plug error (ignored it). Then some days later was checking for faults and had 3 total glow plug errors including cylinder 1.

Since it was summer i decided to ignore the glow plug faults and keep driving... until a DPF becoming clogged message appeared in CCC.

Can also confirm DPF will not regenerate when there is glow plug error.

Had to replace glow plug module but all the glow plugs were fine. However plugs themself had different resistance.

[335dlci]

Sadly it has been confirmed via BMW technical training manuals and any fault in the dde can prevent a regen

[Kozlio]

Glow plug control module replaced by indie. Intake didn't need to come off (luckily). Glos plug codes gone.
Had 3 regens since and near 1,000 km on a tank on Interstate from Ontario into Kentucky. Ac on.
Random x5d fella refueling at sunoco behind me didn't know about ecu tunes. Illuminated him on malone, whetstone and jr.
Cheers

[AlexH503]

Hello everyone new to the forum,
I have a 2010 bmw 335D and got the SES light. When I plug in my OBD2 I get code P066B cylinder 1 glow plug control circuit high. I have read that the control unit for glow plugs goes bad and I'm at about 66k miles. My particulate filter also has high resistance and from my research once the control unit and glow plug go bad it starts fouling the particulate filter and fixing the first issue usually fixes the other one. I'm planning on changing all my glow plugs and control unit and cleaning out the particulate filter. Thoughts?

[Yozh]

Do you get a code for the DPF?

[montr]

Originally Posted by AlexH503

Hello everyone new to the forum,
I have a 2010 bmw 335D and got the SES light. When I plug in my OBD2 I get code P066B cylinder 1 glow plug control circuit high. I have read that the control unit for glow plugs goes bad and I'm at about 66k miles. My particulate filter also has high resistance and from my research once the control unit and glow plug go bad it starts fouling the particulate filter and fixing the first issue usually fixes the other one. I'm planning on changing all my glow plugs and control unit and cleaning out the particulate filter. Thoughts?

My 335d has now 125K miles. When I got the codes for 2 glow plugs at 86K miles, I replaced only the glow plug controller. That fixed the problem. It is likely the controller, not the glow plugs.

[AlexH503]

Originally Posted by montr

My 335d has now 125K miles. When I got the codes for 2 glow plugs at 86K miles, I replaced only the glow plug controller. That fixed the problem. It is likely the controller, not the glow plugs.

Originally Posted by montr

My 335d has now 125K miles. When I got the codes for 2 glow plugs at 86K miles, I replaced only the glow plug controller. That fixed the problem. It is likely the controller, not the glow plugs.

Thank you so much for your help. I guess I can change the controller and that doesn't fix it do the glow plugs. I'll also to the particulate filter cleaning. I appreciate you sharing your experience.

[AlexH503]

Originally Posted by Yozh

Do you get a code for the DPF?

Originally Posted by Yozh

Do you get a code for the DPF?

Yeah. I'm planning on doing a cleaning for it next weekend. Changing my glow plug tomorrow. If it's not fixed my changing the glow plug I'll switch out the controller.