Instrument Cluster Lights (Mostly) Not Working

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
TheRedScourge
Settled in member
Reactions:
Posts: 16
Joined: Wed Jul 28, 2021 7:21 pm
Instrument Cluster Lights (Mostly) Not Working

Post by TheRedScourge » Thu Jul 07, 2022 3:48 am

I'm back with more random issues on my NC23. The gauge cluster lights don't light up. When I got it, it was the same. I assumed it was blown bulbs, but I've since replaced them and it's the same. No lights on the speedo, tach, or coolant temp gauge. I am however getting lights on the little panel with oil, neutral, high beams, etc. The headlight works. I'm just running the left one as I'll be using an endurance style nose fairing. Rear brake light works, although something is up with the front brake switch, separate issue I'm sure. I found no obvious damage to the wiring harness. The fuse box is missing it's lid, but in checking the wiring diagram in the Haynes manual, it appears there isn't a fuse for the gauge cluster. Does it rely on the headlight fuse? Battery is fully charged. All other electrical components appear to be working just fine. Any ideas on where to start?

cbr400rrn
Site Supporter
Site Supporter
Reactions:
Posts: 1267
Joined: Tue Apr 29, 2008 9:37 pm
Bike owned: NC29 CBR600F
Location: Lancashire
Re: Instrument Cluster Lights (Mostly) Not Working

Post by cbr400rrn » Thu Jul 07, 2022 11:27 pm

I’ve tried looking at the wiring diagram in the Haynes manual and come up drawing a blank. See if you can find if anything else doesn’t work by looking at the wiring diagram

TheRedScourge
Settled in member
Reactions:
Posts: 16
Joined: Wed Jul 28, 2021 7:21 pm
Re: Instrument Cluster Lights (Mostly) Not Working

Post by TheRedScourge » Fri Jul 08, 2022 12:33 am

cbr400rrn wrote:
Thu Jul 07, 2022 11:27 pm
I’ve tried looking at the wiring diagram in the Haynes manual and come up drawing a blank. See if you can find if anything else doesn’t work by looking at the wiring diagram
Ok, thanks. I'll do that. I'm wondering if it's a bad ground.

magg
Senior Member
Reactions:
Posts: 1910
Joined: Mon Sep 20, 2010 11:55 pm
Bike owned: VFR400
Location: Blue Mountain NSW Australia
Re: Instrument Cluster Lights (Mostly) Not Working

Post by magg » Fri Jul 08, 2022 3:06 am

Do parking lights work?

TheRedScourge
Settled in member
Reactions:
Posts: 16
Joined: Wed Jul 28, 2021 7:21 pm
Re: Instrument Cluster Lights (Mostly) Not Working

Post by TheRedScourge » Fri Jul 08, 2022 3:17 am

magg wrote:
Fri Jul 08, 2022 3:06 am
Do parking lights work?
What do you mean by parking lights?

MadMotoUK
Familiar Member
Reactions:
Posts: 310
Joined: Tue Nov 24, 2020 12:53 pm
Bike owned: FZR400,600, CBR893
Re: Instrument Cluster Lights (Mostly) Not Working

Post by MadMotoUK » Fri Jul 08, 2022 4:54 pm

Cluster lighting will be powered by the same circuit as the sidelight. Does the sidelight work?

TheRedScourge
Settled in member
Reactions:
Posts: 16
Joined: Wed Jul 28, 2021 7:21 pm
Re: Instrument Cluster Lights (Mostly) Not Working

Post by TheRedScourge » Sun Jul 10, 2022 3:08 am

MadMotoUK wrote:
Fri Jul 08, 2022 4:54 pm
Cluster lighting will be powered by the same circuit as the sidelight. Does the sidelight work?
I finally got some time on the shop tonight. The sidelights are entirely missing. I didn't even know these bikes had something like that. There is a plug and wire with a rubber boot on the other end that came in a box with the bike that may be for the sidelight. I don't have any bulbs that fit it though. I may be able to find a bulb to fit that tomorrow. Any idea on how to proceed with troubleshooting that circuit?

MadMotoUK
Familiar Member
Reactions:
Posts: 310
Joined: Tue Nov 24, 2020 12:53 pm
Bike owned: FZR400,600, CBR893
Re: Instrument Cluster Lights (Mostly) Not Working

Post by MadMotoUK » Sun Jul 10, 2022 5:29 pm

TheRedScourge wrote:
Sun Jul 10, 2022 3:08 am
There is a plug and wire with a rubber boot on the other end that came in a box with the bike that may be for the sidelight. I don't have any bulbs that fit it though. I may be able to find a bulb to fit that tomorrow. Any idea on how to proceed with troubleshooting that circuit?
It sounds like you have the loom then. The sidelight is a T5 5w capless bulb same as the cluster backlights, the boot pushes into the lower part of the headlamp bowl from the rear. I'd hazard a guess that the sidelight has been removed because it didn't work.

I can't remember if they are on permanently with the ignition or not. In any case, if you don't have a sidelight position on your light switch, it's not an MOT fail so no major stress to sort it before then.

Lack of cluster backlight can be annoying though :twisted:

I'd be tempted to find a switched live from the back of the barrel and run a fresh source to the cluster lights, through a suitable fuse of course. May as well have the cluster lit up permanently with the ignition on.

TheRedScourge
Settled in member
Reactions:
Posts: 16
Joined: Wed Jul 28, 2021 7:21 pm
Re: Instrument Cluster Lights (Mostly) Not Working

Post by TheRedScourge » Mon Jul 11, 2022 2:51 am

Thanks MadMoto. That helps. It's more than 25 years old and I'm in the states, so it doesn't need any sort of inspection. I'll start with the bulb and go from there. I should be able to see power with a multimeter right? I poked the prongs into each terminal with ignition on and got no reading.

CB1pod70
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 465
Joined: Thu Apr 09, 2015 1:55 pm
Location: Gravesend
Re: Instrument Cluster Lights (Mostly) Not Working

Post by CB1pod70 » Mon Jul 11, 2022 12:35 pm

MadMotoUK is correct, they are fed off the same supply as the sidelights. There should be a brown / white wire on the plug which the speedo unit connects to - check this has power when the side lights and then main lights are on. If not chase the wiring back to the switchgear on the L/H handlebar


Post Reply