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So took the switch out and took it apart to figure out how it works. When I took it apart was excited to see carbon build up that could be cleaned. Sadly didn't fix the issue.
I suspect either a bad transistor or diode...I could try to re-solder all the transistors, but debating even bothering.
BUT
I did take pictures on how to dissect the switch, and MAYBE for next person, a simple cleaning of the contacts could help
Try bending the tabs so they touch a spot on the board that isn't worn away? Although, an unlikely fix.
Great pics btw
:-(....that didn't work.
looking at the board, they are all diodes and they all checked out.
I am starting to wonder if it is a particular fuse. I found like 6 fuses in the fuse diagrams that state headlights...I found a couple of used switches on ebay I could try.
Checked ALL of the fuses in the driver's side box, as well as the fuse box under the plastic battery tray (the larger box (on firewall) and the smaller box...the larger box is a PIA to get to )
No blown fuses...I GUESS a new-to-me switch is in order.
Great shots! I wish more folks took it to this level. It *could* be a cracked solder joint, but doubtful since the issue is not intermittent. I just repaired a flakey digital gauge cluster on an 06 Honda Civic I purchased for my daughter. Portions of the middle digit on the digital LCD Speedo were intermittently flickering. I picked up a hot air solder station on Amazon for $80, sucked out the old crappy solder with with some copper wick, and re-flowed all suspect LCD pins with high quality Kester solder. Gauge cluster now works flawlessly. I already had high quality electronics flux, solder, and wick, so my only cost was the Hot Air station and some of my time. Totally worth it when compared to purchasing a new OEM cluster.
Hope the new switch works! Have you tried putting 12V directly to the high-beam circuit this position of the switch activates through the harness plug to verify it's not some other fault?
-Icer
Great shots! I wish more folks took it to this level. It *could* be a cracked solder joint, but doubtful since the issue is not intermittent. I just repaired a flakey digital gauge cluster on an 06 Honda Civic I purchased for my daughter. Portions of the middle digit on the digital LCD Speedo were intermittently flickering. I picked up a hot air solder station on Amazon for $80, sucked out the old crappy solder with with some copper wick, and re-flowed all suspect LCD pins with high quality Kester solder. Gauge cluster now works flawlessly. I already had high quality electronics flux, solder, and wick, so my only cost was the Hot Air station and some of my time. Totally worth it when compared to purchasing a new OEM cluster.
I have a similar issue with my wife's G35. Affects the fuel gauge too...reads too high when down pass 1/2 tank of gas used. The fix is exactly like what you did...BUT to get to the board is not for the faint of heart.
My fix is two fold
1 - reset trip odometer everytime I fill up with gas and fill up at around 320 miles
2 - added resistors at the fuel level sender on the driver's side. So at full it reads slightly less than F, and goes down pass the 1/2 mark...(I don't trust the gauge)
Hope the new switch works! Have you tried putting 12V directly to the high-beam circuit this position of the switch activates through the harness plug to verify it's not some other fault?
-Icer
I have not tried that...a little scared to do that to be honest as I am not sure what is what, and don't want to short out the ECM/PCM
At rest and with lights turned on, some of those contacts are closed at the top of the circuit board.
When I get the new-to-me switch, and it works, I will be testing the diodes to see if the numbers on the old are the same as the new.
right now the readings are OF one way and .5v the other way...which seems right to me.
crossing my fingers that the new-to-me switch fixes it. I think it is a 50/50 outcome to be honest.
Yes, a wiring diagram is definitely a good idea when messing around with a Power Probe or other type of tool. This switch is most likely a low current circuit that activates the lights through a relay.
-Icer
Yes, a wiring diagram is definitely a good idea when messing around with a Power Probe or other type of tool. This switch is most likely a low current circuit that activates the lights through a relay.
-Icer
I don't doubt that the switch energizes a relay.
I would think that it would be the same relay that is energized when the high beams are turned on....BUT you got me thinking MAYBE it IS a different relay.
Thankfully the new-to-me switch is only $20 and not $150 for a NEW one.
Ugh more stuff to check ....I REALLY hate the placement of the fuse box on the driver's side kick panel.
Well dang...the new-to-me switch did NOT fix the problem. The good news, it is less worn than mine.
Gotta do some research as to where the replays are ....I suspect BACk on the firewall under the battery cover.
UPDATE:
Well found 2 relays in the big fuse box, behind the battery (you have to remove the battery cover and the plastic that bumps up against the windshield)
1 for Low and 1 for hi....switched them and no difference.
found a few fuses for headlamps (low left , low right, hi left and high right) and all were fine.
Whew...what a goose chase. Ultimately it was a bad terminal within the connector for the headlight switch,
Starting from the top down, Pin 4 is the pin that sends the signal to the BCM to turn hi-beams on. BTW the momentary hi-beams is called PASSING in the service manual.
Pin 5 is the pin to tell the BCM to KEEP the hi-beams on.
Looking at the white connector on the clock spring pin 4 looked odd like it didn't have a terminal...Hard to see with my eyes.
M29 is the connector behind the Wiper Switch. It combines the Headlight Switch outputs along with the wiper/washer outputs. The wires go around the behind the clock spring.
M90 is the large connector for the BSM which is right below the fuse panel on the driver's kick panel.
This is my second clock spring in a few years, and YES it was a cheaper Chinese model from Ebay. I would guess that my PASSING lights have been gone since the replacement of the clock spring earlier this year.
Nice write up once again and congrats on staying persistent and solving the issue on your own! I'm glad it wasn't a shorted/melted/corroded wire, just an open circuit due to mfg defect. So, be honest, how long did it take you to trace this down once you had the wiring diagram?
Cheers!
-Icer
Nice write up once again and congrats on staying persistent and solving the issue on your own! I'm glad it wasn't a shorted/melted/corroded wire, just an open circuit due to mfg defect. So, be honest, how long did it take you to trace this down once you had the wiring diagram?
Cheers!
-Icer
My buddy got me the diagram. Finding the BSM took a little bit of googling and just assumed that M90 was the large plug on the BSM. The damn diagram didn't state where M29 was, maybe it was apparent to someone reading Combination Switch that THAT was the connector at the wiper/washer switch. If someone knows where it is shown or listed as to where these numbered connectors are, that would be great.
I didn't need to trace the wires from the M29 to M90, as I saw the missing pin in the white connector.
BUT the diagram flow chart would have led me to replace the BSM.
The diagram also doesn't state what each wire on M29 is. THAT would be super helpful...I could have back probed the M29, which is WAY easier to get to than the BSM.
so total hrs in this crap
2hrs inspecting and taking apart the original headlight switch, figuring out what the path way for the PASSING circuit
2-4 hrs researching online for similar issues.
1 hr speaking with my buddy coming to the conclusion that it is either wire or with the new-to-me switch...as the lo-beam and hi-beam worked so BSM it most likely ok
1hr getting to BSM, and searching for M29 (wish I noticed that wire colors on the wiper switch were the same as M29 sooner - LOL)
,5 hrs taking the clock spring out
.5 hrs mapping the pins from headlight switch to which pin on M29
.25 hrs getting the clock spring back in and steering wheel in.
So easily 9 hrs...ugh.....I was about to get a scope and software to see the CAN bus....seriously considered getting a used Consult-II LOL (pricey )
Update: Forgot to include the checking of fuses and relays....add another 2hrs at least
They needed to add checking for continuity between the 8 pins on the headlight switch and certain pins on M29
Which BTW are
With all the time and effort that went into this thread, I sure hope it helps someone in the future!
I hope so too, LOL
when something doesn't work on my car or boat, I tend to fix it and learn as much as I can about the thing that broke.
Not sure if you know what a VRO is on the old evinrude/johnson outboard motors from 1984 - 2000, but I went as far as finding the patents and speaking with the guy that patented it for OMC. :-)
09-07-2022, 11:30 AM
FIXED - Do I need a new light switch - 2005 coupe
