How to: Change 407 Speedo illumination

[battlestar]

This was done before for 307, but i thought it would be good idea to do one up specificaly for 407.

My idea was to do replace them all with reds, i loved the rental A4 (B8) dash, so i thought why the hell not. Fairly easy to do, just needs bit patience and steady hand.

Tools needed:
- Peugeot 407 (maybe applies to Coupe)
- Soldering iron and solder
- Soldering iron pump
- SMD LED 3528 PLCC-2 (for km\h rpm dials)
- SMD LED 3528 PLCC-4 (for mfd)
- SMD LED 0805 (for needles)
- Plastic opening kit (or a knife )
- Long, thin screwdrivers
- Sewing needle
- Tweezers


I didnt write up the amount of leds you need, as they are pretty cheap, easy to break and depends on what you want to do.. and i also forgot. under the mfd there is 16 Leds, 8 red (which don't seem to light up ever) and 8 orange. Under each of the motors for dials is 1 led, red. And there is around 10 orange Leds under the km/h and rpm scales. Since I wanted mine to be all red i just changed 8 for mfd and all under km/h and rpm scales. Always get loads extra, they are easy to destroy. :-)

When buying leds pay attention to luminous output of leds. Originals are around 500-550mcd, all I got were as close as possible to that, otherwise you will end up with brighter and darker areas.


Before I start, I'd like to thank stubbo, daffyduck, johnh and everyone else who contributed to original 307 thread which gave me enough data and courage to do this.

[battlestar]

Step 1.
- Move the steering wheel all the way down and out.
- Move aside the fascia surrounding the speedometer using the plastic spatula.
- Push screwdrivers thru the 3 small holes on top of speedo until they hit the tabs circled in red. (Pic 1)
- Pull down the end of each screwdriver to unlatch the metal bits holding the speedon in place.
- Pull the speedo out gently and disconnect the cable by pulling the small black lever on the connector.



Step 2.
- Remove the plastic casing by unlatching 4 tabs on top and 4 on bottom of speedo.
- Slide out the speedometer from the casing.

Step 3.
- Take a picture of dials and needles to record the correct position of needles.
- Using the plastic spatula, remove each of the speedo needles, taking care not to rotate them, but just to lift them.

Step 4.
- Unlatch the tabs circled in red to free up pcb to slide up. (Pic 2)
- Slide up in direction of arrow to release lower 4 latches.
- Once free, take care not to damage the mfd.



Step 5.
- Note the exact placing of each of the needle motors.
- Using the thin needle push in the insides of the tabs holdign the motors on the pcb. (Pic 3)
- Remove needle motors, again noting where each one was located, not to mix them up once returning.



Desoldering the LEDs

- To unsolder desired LEDs heat up just one contact.
- Remove molten solder using the desoldering pump. (not to be used for penis enlargement)
- Heat up the other contact and lift off the LED, noting the orientation.
- For larger 3528 LEDs, orientation is defined by the triangular notch (Pic 4)
- For smaller 0805 LEDs, orientation is defined by the green arrow printed on the underside



Soldering new LEDs

- Heat up the remaining solder from the 2nd contact on the pcb.
- Gently bring down the new LED using the tweezers (in right orientation)
- Heat both the remaining solder and the contact of the led.
- Once both are sufficiently hot, should take no more than 1-2 seconds, lower the led onto the molten solder.
- Hold it in place untill the solder solidifies, locking in the LED in position.
- Now you are free to solder the other contact of the LED
- To do that, simply heat up both the LED contact and PCB contact and once both are sufficiently hot, push in 1-2mm of solder between the contacts (not onto the soldering iron)

[battlestar]

Same procedure applies to the 3528's with 4 contacts, just take care not to create short between them, as they are very close.

Take care of the orientation of leds, if you reverse polarity, they will not work.

Take care when soldering new LEDs, do not heat them up more than 5 seconds, as that might damage them. And especially once they are hot, after or during soldering, do not press down onto the lens, as that WILL destroy them.

For changing the MFD leds, you need the PLCC-4 3528 LEDs with 1 anode and 3 cathodes. These are not dual leds, or anything like that. LEDs under MFD are mixed, there is 8 orange and 8 red ones. Pic 5 shows their positions in respective colors. I have not seen the red ones light up, ever. So i am not sure if there is point in changing them if you want mfd color other than orange/red.



To reassemble the speedometer, work in reverse starting with step 5. Pay close attention to replace dials motors back to their original place, and to replace dials in pretty much exact position where they were before removal. Push them in, taking care not to spin the dials or the motor. I dont know how zeroing or calibration works on this speedo, so i avoided to make any changes.

And thats pretty much it. Any questions, feel free to ask.