Hi, I have a 94 3.0 4x4 Toyota pickup.. I started working on it and noticed mil don't come on with key on position.. took cluster out and no bulb was in it.. I put one from the brake light in it and it blew.. I checked both sides of socket to see if I was getting 12v and I am getting 12v but on both contacts... Does this mean the board itself is shorted?? That's the only thing I can figure and I need another cluster... There is a screen on the back of the cluster that says -.. it's a good ground and the brake light side of the cluster works fine.. any ideas?? The check engine light is important

 

Back up, try again. Incandescent bulbs are dead simple. All of the bulbs on your truck are 12v. One can be "blown" by significant over-voltage (24v?) or mechanical shock. But putting 12v on both contacts will mean it just doesn't light (no current). It can't blow the bulb.

One side of the socket is always 12v with keyon (through GAUGE and integration relay). B-O pin 8 of C11. The other side (V pin 9) connects to the ECU AND the W pin of the diagnostic connector. The bulb is illuminated by grounding W. So start with the easiest test. Measure the voltage to ground at W on the diagnostic connector. This is just the sanity check; with the bulb out you should get 0v, with the bulb in about 12v (through the bulb). Then check the voltage from W to 12v. With keyon, engine off, W should be at ground, and you should get 12v.


... What does it say?
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​​​​​​​Screen should've been screw.. and it says - negative

 

I'll check all of that when I get home

 

​​​​​​ So... I know I have 12v on both sides with key on no bulb in.. the bottom should always be 12v the top should ground through w pin right? Key in on position grounds w am I correct
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keyon causes the ecu to ground W. Once the engine starts, W is no longer at ground (I don't know if it's high-impedance or 12v, but it won't ground the bulb).

I don't know about top and bottom; you may be able to trace through pinout or wire color.