Analog instrument clusters? HELP!!!!

Hi everyone! How's it going?

New to the forum but have gleaned a lot of great advice from the past on different vehicles.

I have a 2001 Mazda B3000, SE7. Had to replace a few of the illumination bulbs in the instrument cluster a while back, as most of them were burnt out. But now, the instrument cluster doesn't light up when driving at night or early morning. The tail lights work, the fuses appear to be fine, the turn signal work, cabin light works, hazards work, and headlights work. Plus the high beam light, seat belt warning light and check engine light comes on until the vehicle gets up to temp, same as always. But oddly enough, even when I set the speed control, the activator light on the instrument cluster doesn't come one, albeit, very, very slightly. Does anyone have any ideas on what the issue may be and how I can fix this?

Big thing is that I've read prior that even a new licence plate bulb install can short a circuit, and I put in two new ones as only one was burnt and the other was foggy inside the bulb.

The other thing I'm curious about is headlight switches and dimmer switches and how they're adversely linked to the fuse panel. How does one affect the other and how can one diagnose without sorting through miles of wiring?

Sounds like you may have missed a ground when installing the instrument cluster, or maybe a wire is loose in the connector harness. Do other dash panel lights come on as usual with the headlights, such as the HVAC control backlighting and radio button backlighting (assuming the stock radio)?

I trust that you've adjusted your interior illumination dimmer switch to make sure you don't just have it dimmed all the way.

Also, what you do mean about how the headlight and dimmer switches are "adversely" linked to the fuse panel? You want them linked to the fuse panel so if there is a problem, the fuse blows rather than the wiring (and possibly vehicle) overheating and starting a fire.

-Rod

Sounds like you may have missed a ground when installing the instrument cluster, or maybe a wire is loose in the connector harness. Do other dash panel lights come on as usual with the headlights, such as the HVAC control backlighting and radio button backlighting (assuming the stock radio)?

I trust that you've adjusted your interior illumination dimmer switch to make sure you don't just have it dimmed all the way.

Also, what you do mean about how the headlight and dimmer switches are "adversely" linked to the fuse panel? You want them linked to the fuse panel so if there is a problem, the fuse blows rather than the wiring (and possibly vehicle) overheating and starting a fire.

-Rod

Hi Rod,

Thanks for the response back. Appreciated.

Well, the stereo backlighting works great. The instrument cluster grounds? There's only three connectors for the instrument cluster, so I'll make sure that I check the wiring in the harnesses there. No other lights come on. Just the stereo, the headlights and the brake lights when the brake pedal is pressed. The HVAC lights don't come on however.

And yes, I've tried the dimmer switch, but I guess it might be worth a try to look at the wiring for that too.

Ultimately, I guess I'm also just wondering, as far as the fuses go, if the under the hood, in the fuse box there, if the black boxes (relays, right) might be toast? Are they easy to acquire, and also, how can I test if they might be fried? Pardon my naivette, but vehicle electronics is something I'm wanting to learn more about and don't trust the mechanics in the small town I live in.

J