Suzuki Club UK

I believe the fault is the alternator. Looking at this diagram the 3 lights in question will light when the alternator is supplying ground. I assume the handbrake warning and fluid level warning light up with ignition on but engine not running as a test function (The are 2 diodes shown which appear to do this). With the engine running the brake warning circuits should operate as normal as the ground should be taken away (or more likely become positive). My money is on the alternator is fecked, but hell what do I know .

Hi Darrell,

Thanks for the reply.

Once I turn the key to acc, ign or start the lights are on the dash. Interestingly the hand brake switch wiring has been removed altogether by the previous owner so the handbrake light shouldn't function at all. (I may have to rewire this so that the handbrake light does work for MOT?)

Thanks for the wiring diagram, I'll have a look and see if I can make sense also.

I've noticed that when the engine is running and I disconnect and the reconnect the alternator it makes a light grinding noise. The noise is not very obvious, you cant hear it over the engine on cold start but you can once it has dropped down to warm idle. Not sure if this is normal, not something I've ever noticed before but then it's not that obvious either.

Point to note also regarding the alternator... Yesterday when doing some testing I started the engine and then disconnected the negative terminal on the battery and the engine continued to run without issue. So there is definitely some charge coming from the alternator.

Also, as per one on my earlier posts, the voltage measured at the battery with engine on and off looked sensible.

It seems that if it is the alternator that's the issue, it is a ground that is draining the battery when off and causing the dash lights to stay on when running.

I think I'll just buy a new alternator and hopefully fix or at least rule it out.

I had the same issue after the battery went flat, after bump starting it the engine started, but everything worked in reverse. Everything that was switched off was now switched on, and everytime I accelerated it would bog down! New battery and everything was happy.!

The bottom light is your handbrake light, there’s a switch on the handbrake itself, the wire might just be earthing somewhere.

Check your brake fluid level there’s a diode somewhere in then wiring (i have been trying to work out where it actually is for years but it seems to be hiding in the loom somewhere) and when it fails and the brake fluid level is low then it causes your battery light to come on.

Also you don’t need the handbrake light to function for the MOT so just try to find the wire and blank off the end so it’s not earthing out. It runs through the sill on one side and comes out to run under a front seat to the handbrake.

ScottieJ wrote: ↑

Tue May 08, 2018 9:58 pm

The bottom light is your handbrake light, there’s a switch on the handbrake itself, the wire might just be earthing somewhere.

Check your brake fluid level there’s a diode somewhere in then wiring (i have been trying to work out where it actually is for years but it seems to be hiding in the loom somewhere) and when it fails and the brake fluid level is low then it causes your battery light to come on.

Its hiding in here..

That’s not the same as my brake master cylinder cap..... it’s been swapped to a vitara master cylinder, same cap as on later SJs/samurais.
Maybe that’s why I can’t find it

I’ll have a look on my Lwb samurai, see where it is on there, that has the same cap as my Vit MC

Cheers for reply's guys...

Wiring to handbrake switch has already been removed. Haven't found what's left of it yet but I'm not sure it's the issue anyway.
Good to know its not needed for MOT though, thanks!

Pretty sure it's not the master cylinder low brake fluid warning as when I take the reservoir cap off and operate the float the brake warning light on the dash (that's already illuminated) gets a little brighter. This to me indicates that the 3 lights are being powered from somewhere else.

I've now taken the alternator off and done the diode test with a multi-meter. Its showing continuity both ways, which indicates that a diode is gone?

Battery seems fine now that its been on a trickle charger for a few days. Back to a healthy 12.6v and turns engine over at a good speed.

So I've now priced up a new alternator and just need to order that from local motor factors. Will let you know if that does the trick.

Cheers,

Larry

Hey guys,

Was unable to source alternator through my local factors as none were in stock but they directed me to local autoelectrician who managed to repair current alternator for 40 quid. Just refitted it and dash lights are going out as they should!!!

Woohoo!!!

Thanks for all the suggestions, in particular the one that sent me after the alternator as it would have taken me a while to suspect that was the problem!

MOT soon hopefully!!