Car electrics. Anyone here any good?!

[Cozzer]

Perhaps I should say "any good at explaining in Noddy fashion"!

In UK, Honda 2004 CRV.
Changed the dashboard cluster lights as 2 of 'em had blown.
Result = all the "warning" lights work - handbrake, seatbelt, SRS, oil and so on.

The 4 gauges/dials work - speedo, fuel level, temp, revs - but don't light up.

I've turned the bulbs 180 in their holders.
I've turned the holders 180.
I've checked the 7.5A fuse governing "gauges".

What else can I look at?!

 

[Spectric]

Hi

Just brought a 2006 CRV because it is a more basic vehicle with minimal electonics to cause headaches unlike my last vehicle which was a Peugot.

Remove all the bulbs and refit one at a time and see what happens, are they the right bulbs, check you have not damaged any connectors and they are fully inserted.

 

[Cozzer]

Thanks, Spectric...
The bulbs have been in/out/turned so many times, my thumbs ache from lifting the little tabs on the blue and green multiconnectors at the top!
At least I haven't got to worry about the cruise/front fog (top left) - that's empty, as are all the A/T gear jobs.
Looking at your graphic, it's the "gauge lights" that aren't working. I saw another video stating that the immobilizer bulb "controls" all the others - i.e. if that blows, they all cease to work - but mine certainly lights.

 

[Lorenzl]

Is the ground still connected? Crack in a track on the pcb?

You could do with a multimeter but I used to just use a lamp on two pieces of wire when I was younger to check for power. Put it on the positive side of lamp holde and touch it to any bare metal/screw and it should light up - 12v lamp of course.

 

[guineafowl21]

The dash illumination bulbs usually come on with the sidelights, so check those are working. Some cars have a pot to vary the brightness, so worth a check for that and if you have voltage there.

The most useful tool for this sort of thing is a 12V test light - attach to battery -ve, and it will light up when touched to +ve, and vice-versa. Also good for checking fuses quickly in situ - attach to earth somewhere, and touch each side of the fuse. Should light up both sides. One side = fuse bad. No sides = fuse not powered. You can check every fuse on the car in minutes.

 

[Cozzer]

Thanks, gents... In answer to your questions, in no particular order...

Have got goodish Misco multimeter.
Thankfully (!), this model doesn't have a dimmer for the display. (The Honda, not the multimeter!)
Doubt the track problem - the whole PCB is enclosed in plastic, and has been from minute one. (That's not to say it can't be opened up, just that I haven't had need to to replace the bulbs)
As regards touching the + side of each holder, they're not marked. What you see in Spectric's diagram above is what you get. Hence my confusion....you can re-orientate the bulb 180, but you can also rotate the holder 180!

Something else I should mention - the 4 gauges lit before the operation. What had failed was one indicator and the odometer bulb. I thought I might as well replace all 10 rather than have to rip all the panels off again in a month's time when the next failed.

And guess who's kicking himself for being a smartar5e now....



edit... and yes, a 12v test lamp. Just found it in the cellar!

 

[clogs]

is the wiring connection onto a hard pcb board or it it a flat flappy wire kinda thing.....either way those circuits /connector connections are very delicate....
had a similar prob in the past and just solderd a hot wire or two, by-passing the individual connection to get em working...

 

[Lorenzl]

edit... and yes, a 12v test lamp. Just found it in the cellar!

I bet your glad you didn't throw that away all those years ago now

 

[Spectric]

This wiring diagram shows how the tail light supply is derived from the tailgate relay, bear in mind like many vehicle electrical systems they use low side switching so the light switch grounds the relay to operate.

This is the positive supply to the dash lights, I would have thought you do have a brightness control which on mine is near the fuel gauge and this provides the ground side.

 

[Spectric]

This is the actual cluster and the five bulbs, Red/Black on B7 is from the tail light relay, the actual function is provided by a mosfet to ground. The brightness control works via the gauge assembly cpu to switch this mosfet. On mine when it reaches max or min brightness levels it beeps.

 

[Cozzer]

Y'know how they say that the best ideas usually occur to you when you're on the toilet?!
Well, relax....this isn't one of those!
Gave up trying to understand the car as night fell, and decided to drag the dog out into the drizzle.
I wasn't actually thinking about the car at all, but standing in the gloom waiting for him to relieve himself for the twentyeighth time, something hit me....
It might not be the bulbs/circuitry at all.

The left stalk works the indicators, but the "end" of it operates the exterior lights.
The dashboard dials/gauges don't light until you turn the lights on.
Ergo, it could more likely be the stalk/light switch malfunctioning.....

Got home, got in the car, started it and pulled the stalk towards me (so as to let you out of your drive by "flashing" you, as t'were). The headlights flashed, and the blue full beam light on the dash lit momentarily.
Then I tried pushing it away, as if driving with full beam.
The lights worked, but no blue full beam light on the dash.....

More tomorrow, no doubt....

 

[Fergie 307]

Not sure if it applies in your case but some vehicles need the electronics reset when certain components have been disturbed. Might be worth disconnecting the battery for a few minutes, then reconnect. And typically your bulbs are not polarity sensitive, which is why it doesn't matter which way round they go.

 

[manglitter]

Dd you

Y'know how they say that the best ideas usually occur to you when you're on the toilet?!
Well, relax....this isn't one of those!
Gave up trying to understand the car as night fell, and decided to drag the dog out into the drizzle.
I wasn't actually thinking about the car at all, but standing in the gloom waiting for him to relieve himself for the twentyeighth time, something hit me....
It might not be the bulbs/circuitry at all.

The left stalk works the indicators, but the "end" of it operates the exterior lights.
The dashboard dials/gauges don't light until you turn the lights on.
Ergo, it could more likely be the stalk/light switch malfunctioning.....

Got home, got in the car, started it and pulled the stalk towards me (so as to let you out of your drive by "flashing" you, as t'were). The headlights flashed, and the blue full beam light on the dash lit momentarily.
Then I tried pushing it away, as if driving with full beam.
The lights worked, but no blue full beam light on the dash.....

More tomorrow, no doubt....

Have your headlights on when you tried putting your full beams on?
If not they will not stay on...

Also your guage lights will not be lit without at least your sidelights on

 

[pe2dave]

"Dash lights brightness controller" - Is it working? Is it open circuit? That would kill the lights?

 

[Cozzer]

"Dash lights brightness controller" - Is it working? Is it open circuit? That would kill the lights?

There isn't one. Not on this model.

Messed around for another couple of hours yesterday afternoon, and roped in a pal of mine who's used to sorting out electrical stuff on mowers and the like. Basically he checked everything I'd already done, and was also none the wiser.
Only thing left - having checked every in-car and under-bonnet fuses - to verify as working are the relays.

I can think of better things to do on a Saturday afternoon....

 

[Gerry]

Powers and grounds is the first place to start using a test light so it loads the circuit not a multimeter.

Gerry

 

[Spectric]

You need to take this from a logical perspective and one thing at a time otherwise you may miss the actual fault. The first thing I would check is the relay in the fuseboard under the dash, is it operating when you turn the sidelights on. If this relay is operating then check you are getting voltage at pin B7 on the cluster connector, a Red wire with Black tracer. If you have power here the fault is on the cluster, if not then check fuse 2 under the bonnet.

 

[John Brown]

New car.

 

[Cozzer]

Cheers, Spectric....
The in-car fusebox is a right pain!
Underneath the steering wheel, at the side of the central console. The only way I can get to it is by keeping the passenger door open, sliding on my right side across the seat and central tray, before twisting the top of my torso into the driver footwell and looking up! It helps if you also have a torch down there!

The under-bonnet is a breeze in comparison, except trying to interpret the symbols on the inside of the cover!

The sunshine got the better of me earlier - 30 minutes scratching my head with the bonnet open, and then I went to the pub for a brace of Guinness!

 

[woodieallen]

Cheers, Spectric....
The in-car fusebox is a right pain!
Underneath the steering wheel, at the side of the central console. The only way I can get to it is by keeping the passenger door open, sliding on my right side across the seat and central tray, before twisting the top of my torso into the driver footwell and looking up! It helps if you also have a torch down there!

The under-bonnet is a breeze in comparison, except trying to interpret the symbols on the inside of the cover!

The sunshine got the better of me earlier - 30 minutes scratching my head with the bonnet open, and then I went to the pub for a brace of Guinness!

Just a brace ? harrumph....lightweight