Suspension sinks on Sundays! C5 X7 that works hard + 206 GTi HDi (and 406 Coupe and 306 HDi). - MattBLancs

[ozfrog]

Very odd, I can't wrap my head around why PSA "hid" the regen process. It's key to the engine keeping in a running condition, but a simple "regen in progress" light wasn't considered. Very odd.

On Reddit a few days ago, I saw this headline:
I created a way for me to know when my diesel (1.6 BlueHDi) is regenerating

It intrigued me, so I read further. (I've copied and pasted the person's post directly. All spelling and grammar mistakes are not mine!

If you're interested in reading the original post and comments, as well as viewing the three images, I'll post a link.

I installed a red LED into the mirror of my car and soldered it to the wires for the heated mirrors.

Recently I had to replace my DPF because it was clogged (which in turn also wrecked my turbo unfortunately) after only 80k km. I often do long drives on the highway, so I was confused why it clogged so quickly. Only thing I could think of was either me occasionally turning the car off whilst it was in the middle of a regen cycle, or something else causing the regen cycle to not fully complete, mechanic couldn’t find any weird things in the log, so I decided to do something myself. I’m hoping that with this indicator, I’ll now have an idea of when the car is regenerating, so that I’ll leave the car running, or shift into a lower gear for more rpms and a smoother regen until the cycle is complete, hopefully leading to a longer lasting DPF.

For those wondering why I did it like this:

Whenever the car regenerates, it turns on the heated mirrors and a bunch of other electrical things in order to use as much electricity as possible, forcing the engine to work harder and the exhaust to get hotter, this allows the car to burn off all the collected soot in the DPF. By hooking up an LED to the heated mirrors, I now know that if the light turns on on its own, the car is in a regeneration cycle.

If anyone else is interested in doing this, I can highly recommend it.

[Huskyxantia]

Ive read that and also seen it being debunked as to some cars have auto heat setting which will switch on the heated mirrors then that led comes on too.

[ozfrog]

Ive read that and also seen it being debunked as to some cars have auto heat setting which will switch on the heated mirrors then that led comes on too.

I presume you're referring to what I posted.

Wouldn't that LED coming on be dependent on how things were wired?

[Huskyxantia]

More than likely I guess if it was wired to the mirror live then yes

[Rp0thejester]

So.... It only works with heated mirrors? There must be another way to tell. Someone with vehicle electric smarts (not me) can surely figure out how to wire something together. Something in the OBD slot could be useful.

[MattBLancs]

My understanding is the electric heated mirrors route is easy option to tap into and get an LED in the driver's eye line.
Regen cycle on going = car brings on lots of electrical load to help the engine build heat (including heated mirrors, and screen:

If you didn't have electric mirrors then the heated rear screen is also brought online (without the dash heated rear screen light coming in, sneaky!)
So you could tap into heated rear screen wiring for an LED if you didn't have heated mirrors.

Also brought on during regen is the glow plugs.

I believe (those fitted with one) the "air doser" also flicks over to bypass the intercooler, so potentially there is something there which could be tapped into

[Huskyxantia]

It also uses the rear window dimister, I'd take a live from one of the dpf sensors as they must trigger something

Found this