I just got a call from my mechanic who told me what is wrong on my 2002 Volvo s40. The central electronic module (CEM) needs to be replaced.

My drivers side headlight is quite fluky. I have daytime running headlights. My driver's side headlight sometime works and sometimes it does not work. I have no problem with the passenger side headlight.

The CEM new costs about $ 900.00. That is way too much. I believe that I have found a used one Ebay for about $ 70.00. That is much better.

The problem is the relay on the CEM for the drivers side headlight is broken and works sporadically. Hence, I need to replace the CEM. I believe that I can get away with this.

Is this a good idea? I mean getting a used CEM, part number 30621304 instead of spending a whole lot on money or a new one.

Is there an easier way to fix this? Can I just replace the relay that is not working correctly or must I replace the whole CEM?

Any help appreciated. Thanks in advance.

Respectfully,

Lou Reed

 

I have read that you can replace the relay but have never attempted it. There is one or two threads giving the proper relays.

Here is one thread- https://volvoforums.com/forum/volvo-...w-beams-68391/

Here is a UK thread: Guide: How to replace headlamp relay in CEM - Volvo Owners Club Forum

Another: https://volvoforums.com/forum/volvo-...nt-work-58301/

 

I've replaced the relay without issue. That is very likely your problem. If you can solder, it's an easy fix. If you can't, just buy the relay, take the CEM out and bring it to a TV repair guy for them to solder for you. It's an easy job.

 

I am going to try to solder the new relay in. I am concerned about getting the old one out. I am not going to solder this myself, but I will let someone who solders for a living do it. It seems though that the problem is getting to old (malfunctioning) relay out of the CEM. That requires one to desolder and how is that done.

Is it safe to assume that a TV repairmen who solders for a living can also desolder?

Any help appreciated thanks in advance.

Respectfully,

Lou Reed

 

I replaced the CEM on my 2000 S40 with one from a yard. Cost me $50 and took about 15 minutes to install. Desoldering? there's a tool called a solder sucker (really) that when you heat the old joint it pulls the liquified solder away. slide in the new part, resolder. (don't use too much...) I still have the old CEM - it may still be good (I swapped out the switch at the same time and did the bulbs so I'm not 100% certain if it failed) I can send it to you if interested...

 

Thanks, but I will try and get a solder sucker to pull the old relay out and then use traditional soldering to put the new relay in. The new relay is on it way to me. I should get it in a few days.

I will go from there.


Thanks anyway.

Respectfully,

Lou Reed

 

Soldering/Desoldering are both pretty straightforward. Watch a couple of videos on youtube and you will be an expert in no time. A TV repair guy could do both for you for about $30. A starter kit from radioshack (which includes a desoldering gun) is all you really need.

 

It's true, watch how desoldering is done on Youtube. The hard part is finding a Radio Shack. They are closing stores all over to save money.

 

My mechanic told me that the part number on my 2002 Volvo s40 CEM is:


PICN012W1.


What is this?


I thought the part number was:


JSM1-12V-5. I am not sure what the part number shown first here actually is.


Has the JSM1-12V-5 been superseded by the new part number:


PICN012W1?


Any help appreciated.


Thanks in advance.


Respectfully,


Newport_j

 

I'm confused are you referring to the part # for the CEM or for the relay within the CEM? The relay part # is not a volvo part and depending on the supplier the part number may vary. The JSM part number that you quote above looks like the right generic part # for the relay but note that this is not a VOLVO part so the mech may not have any idea what you are referring to.

Here is a link to the part on Mouser electronics site:

http://ca.mouser.com/Search/m_ProductDetail.aspx?Panasonic%2fJSM1-12V-5%2f&qs=%2fha2pyFaduhAgXY13xv7Z0WKEfIMVaX21xOnJzAk 1Ec%3d

 

I am referring to the part number for the relay only, not the CEM.

The part numbers on the relay are not the same, the part numbers for the ones on the CEM, and the one that I got from Digikey are different.

This may not matter. They certainly look the same, but they just have different part numbers.

The part number of the ones on the board begin with PIC and the one from Digikey begins JSM1.

Finally since there are four of these on the EM, which one is for the relay for the driver's side headlight? It is obviously only one of the four. Is it the one closest or one of the inner ones?

Any help appreciated. Thanks in advance.

Respectfully,

Newport_j

 

Lou - have you read Hudini's posts or what? All the info you need is in the guide, pictures and all.

 

Yes, those posts were quite helpful. It appears that Volvo calls this relay
one thing and Panasonic calls it JSM1-12V-5.

Okay, so now I know that they are the same relay, regardless of part numbers.

The final question is which of the four relays on the CEM represents the drivers side headlight? Please note that I am not talking about the high beams, just the regular headlights.

Any help appreciated. Thanks in advance.

Respectfully,

Newport_j

 

[QUOTE=Newport_j;423127]Yes, those posts were quite helpful. It appears that Volvo calls this relay
one thing and Panasonic calls it JSM1-12V-5.

Okay, so now I know that they are the same relay, regardless of part numbers.

The final question is which of the four relays on the CEM represents the drivers side headlight? Please note that I am not talking about the high beams, just the regular headlights.

Any help appreciated. Thanks in advance.

Respectfully,

Newport_j

 

I must resubmit the question. I have the part JSM1-12V-5, relay for my Volvo. The headlight that is acting up is the driver's side low beam.

The CEM itself seems to have four relays (obviously with a different part number). This one is for the drivers side low beam headlight - not the bright!

So on the CEM which one is that?

Any help appreciated.

Respectfully,

Lou Reed

 

I just thought that I should add that I live in the United States, so when I say the drivers side I of course mean the left hand side.

I thought that this info would help.

Respectfully,

Lou Reed

 

If you scan through the entire thread in Hudini's posting you will find a picture outlining which relay is left lowbeam and which is right.

 

Yes, that is what I need. I saw a diagram on a UK site and found it to say the light was in a different place. Then I realized that that person who made that posting was talking about a sporadically working headlight on the drivers side in Great Britain. Of course that is the left side. That was confusing me.

Thanks you,

Respectfully,

Newport_j

 

Okay, the replacement of the relay for the driver's side headlight worked on my 2002 Volvo s40. It make me wonder if another problem could be fixed in a similar way.


I am unable to use my remote to unlock my Volvo. In fact the red light (on the far right dash upper section) does not flash when I close the driver's side door and lock the car. Manually, of course.


So I noticed that there are a lot of other relays on the CEM.


I am wondering if one might connected somehow be connected to the CEM. If so which one is it?


Any help appreciated. Thanks in advance.


Newport_j

 

Firs thing is to always check your fuses. Surprising that some things are controlled by a fuse and not labelled as such.

Is this the remote that came with the car? Junkyard remotes won't work and cannot be programmed to the car because the proper codes are missing from the remote.

If this remote worked previously but not lately then replace the battery.

Not a clue which computer the remote works with.