CEM-8A12 V50 2009 model

Savi · Post by **Savi** » 05 Aug 2020, 02:47

I have following error.
Any idea how to fix that?
All lights working expect "City light 194" which is led.

Passenger side city light is "dead"

Make:
Volvo
Code:
CEM-8A12
Definition:
Low Beam Left. Faulty Signal
Description:
The central electronic module (CEM) powers the left-hand low beam directly via an output. The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that the power consumption for the output is too low. The diagnostic trouble code (DTC) can be diagnosed once the dipped beam has been on for a minute.
Cause:
Low beam defective or missing
Open-circuit in the signal cable to the right-hand low beam
Short-circuit to supply voltage in the signal cable. F.

Post by **RickHaleParker** » 05 Aug 2020, 08:27

Can you switch the left low beam off with the engine running?

Savi · Post by **Savi** » 05 Aug 2020, 10:20

Post by **RickHaleParker** » 05 Aug 2020, 20:27

Resistance to the low beam has increased. Dirty connector, Bulb socket, Aged bulb or cooked wiring. Left low beam is the Green-Violet wire.

Savi · Post by **Savi** » 07 Aug 2020, 10:33

Little update.

I erased errors via icarsoft and CEM-8A12 is gone. However problems is still there.
I cleaned all connector and bulb sockets.
Right Xenon bulb socket (rust removed).
Wires seems good but you never know.

Pros.

Registered plate lights both working now.
-Earlier left one was dead.

Cons.

Right City light is still dead.

-It seems left headlight don't make calibration when you start car.

Post by **RickHaleParker** » 07 Aug 2020, 18:33

That not a City light it is the parking light. Check the 194 bulb and trace voltage on the Orange-Blue wire.

Savi · Post by **Savi** » 08 Aug 2020, 01:18

You are right. That is parking light

I can't change that bulb

Here is reason why https://forums.swedespeed.com/showthrea ... ion-thread

NOTE (4): 2007+ Cars equipped with "active" bi-xenons may already have LED city lights. In this case, the bulb is not user replaceable (and is already the correct color). You can tell if this is the case because the city light will be a vertical bar close to the same color as the xenon bulb.

I don't really care those led-conversion but this is what i found.

Post by **RickHaleParker** » 08 Aug 2020, 03:50

Savi wrote: ↑08 Aug 2020, 01:18 I can't change that bulb

Open the round cap on the top and see what you find.
Check the open and closed voltage to the lamp.

Savi · Post by **Savi** » 08 Aug 2020, 04:30

https://www.youtube.com/watch?v=ljl1T1zyM-E Volvo V50 2008 model.

And here is what i have under the round cap. https://freeimage.host/i/dE0KI2
I have 2009 model with bi-xenon.

Post by **RickHaleParker** » 08 Aug 2020, 15:30

Did you follow the Orange wire with a blue stripe? In the video it shows the parking light buried under.