Hey,


I've been happy with my 99' Accord 4 cylinder VTEC but recently have been having issues with it. I've been experiencing this problem searching for a solution for the last two months and still no luck. It all started with the climate control not lighting up and engaging when the engine is cold, and after about 5 minutes it worked. Then, after a month or so, whenever the A/C was turned on, all the climate control ***** would start flashing until I turned it off. The heat, and all the climates were working other than that. Just recently, the climate control hasn't even been turning on at all.

Along with the climate control, the compressor fan hasn't been engaging. This meant the radiator is eating up the coolant a lot faster. Luckily I found a glitch; when I turned on my headlights, everything worked. The climate control started working beautifully, the radiator fan started spinning, the coolant level started dropping now that the car knew it was at optimum temperature. This lasted about a month or so and now the climate control, the compressor fans, nor the A/C or defroster are NOT working even with the headlights on!

I am open to any suggests. I've checked all fuses, and none seem to be blown.

 

Could be the unit going bad, do you have a volt meter, shop manual and some time?

EDIT: One thing you can do first is check for codes in the HVAC unit.

 

I have time this weekend. I don't have an OBD for the car, but I was planning on getting one for cheap on ebay that I can use my iPhone on..


For the volt meter, what should I test?

 

You don't need a "reader" to get the HVAC codes.

 

I only see methods of how to get HVAC codes for 2003+ models, I searched but found nothing on the 1999 models..

 

Does yours have the auto feature or not....this pic is for that one, if you don't let me know and I'll dig up the procedure for that one.

 

No auto feature on my 99' Accord EX. I found this video of someone who has the same setup as me, and has the same "flashing" lights when you hit A/C or DEFROST. Well I should say that's how it started about two months ago, but now this darn thing isn't turning on at all.

LINK:

 

Ok, so you have the "non auto" unit.

Sounds like you might have a short in/on the PCB inside the unit. There are some that have repaired theirs buy adding a jumper wire to the board.

 

So after about an hour of looking through the service manual, I believe I pinpointed the source of the faulty problem. The "Heater Control Panel", "Radiator Fan Relay", "Condenser Fan Relay", and apparently the "Read Defroster" were all connect to FUSE 3 - 7.5 amps (Drivers Under Dash Fuse/Relay Box).

How would I test to see if this was truly the source of the problem before I get the jumper wire? ie Volt Meter?

"
Fuse Number
3

Fuse Name
HEATER CONTROL
A/C CLUTCH RELAY
COOLING FAN RELAY

Amps
7.5

Component or Circuit Protected
A/C compressor controls, Air delivery, Blower
controls, Fans, Rear window defogger relay, Seat
heaters (Canada EX)
"

EDIT:: I tried using the self diagnostic tool for the manual A/C but the Recirculation control switch wouldn't light up at all due to it also being on Fuse 3.
The schematic is attached.

 

You could first measure continuity through that fuse. Is the fuse visibly blown? Sometimes fuses blow in a way that's not readily visible just by looking at the fuse.