heater control unit illumination

NCCMUR · Post by **NCCMUR** » Thu Dec 20, 2012 8:49 pm

hi guys

theres bulbs out on my heater control,however upon removal i can only see 2 bulbs on the top of the unit.

can anyone tell me if there are more bulbs connected to the unit?? or am i just missing the obvious???

sorry i dont have any pics at the moment

maybe if someone has the control unit out of the car

cheers people.

Levislude · Post by **Levislude** » Fri Dec 21, 2012 9:47 am

I've got the same problem - just happened yesterday. All of the directional controls light up but hte heat and fan setting ones don't.

Does anyone have any tips before I start taking it apart?

Supermarine Blues · Post by **Supermarine Blues** » Fri Dec 21, 2012 8:14 pm

Parts #2 are the neo wedge blubs.

NCCMUR · Post by **NCCMUR** » Fri Dec 21, 2012 9:13 pm

i did see this on lings

the two holes to the rear of the unit house bulbs (these ones are fine)but on the parts list it assumes your buying 3.

where does the third bulb go?

i've looked underneath the unit and cant see anywhere for bulbs to go

perhaps in the back of it?

i'll try and remove it and check the back of the unit.

CARRisma · Post by **CARRisma** » Sat Dec 22, 2012 12:40 pm

The buttons themselves have thier own bulbs which aren't easily replaced. The backlighting uses 3 bulbs - 2 on top and 1 at the bottom rear.

The backlighting for right hand side 3 of the heater controller unit buttons failed on mine during March 2011. I tried the adjacent bulb and that immediately failed. During April 2011, I bought a replacement heater controller unit from a Prelude being broken in Farnborough, Hampshire for £25.00 (Salazar on PUK), complete with bulbs. The Honda part number is 79500-S30-E01 and the 2011 price is £391.70! Rather than fitting the replacement unit, I tried two of its three bulbs in my original heater controller unit and they immediately failed. I assumed it must be a problem with the socket on my heater controller unit blowing bulbs. During May 2011, I bought 3 spare bulbs for £1.00 from a Prelude being broken in Barking, Essex. The Honda part number is 34354-SB0-003 and the 2011 price is £6.58 each. After fitting the replacement heater controller unit with replacement bulbs, the issue was resolved.

So, it may not be the actual bulb at fault.

I still have my old heater controller unit if anyone wants to buy it?

julienh · Post by **julienh** » Sat Dec 22, 2012 1:54 pm

http://imageshack.us/a/img407/3011/img4363b.jpg

same problem for me a few weeks ago, I only had to scrape a little the wires that are normally in contact with the PCB, and illumination was back !

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sat Dec 22, 2012 11:11 pm

Mine does this.

The heater/fan bit hasn't lit up for the first 3 or however many years I've owned the car. In the last couple of months it's randomely worked a few times, so it wasn't looking like the bulbs.

I have the same problem with the interior light (and puddle lights since I retro-fitted them). Never work on the drivers side, very occasionally working on the passenger side now in the last couple of months.

Right PITA...
I expect I'll be arsed to look into them both and get to the bottom of them eventually.

BlackShadow · Post by **BlackShadow** » Sun Dec 23, 2012 5:10 am

I had the same problem with mine. It's an easy fix (that I was preparing a how-to video for).

If the backlighting doesn't work, but the green LEDs on the buttons do, and if the backlighting bulbs are still good;

You will have to pull the unit apart to expose the circuitboard and re-solder the connections. I followed the lines that seemed to go tot he lights, but in the end, I just re-soldered all the points (to save future problems). It took about 45 minutes from pulling the unit from the dash, to reinstalling it.

All told, it cost me $7 for a soldering gun, and best of all, you don't have to be a pro solderer, or an electronics wizard to do it.