Seat Belt light Stays on

[mamaya3367]

Hello Everyone,

I started probing.  With the buzzer module off and I+ on, I have a seatbelt light on.  I used a light indicator probe and tested the yellow wire leading to the buzzer.  Light on shows power.  I'm thinking I have a short in the foil pcb.  I don't have another pcb to test so I might need to purchase a new one.  Any suggestions? 

[bd]

Unplug the I/P harness from the back of the instrument cluster.  With the ignition ON and the test light clipped to ground, probe the yellow wire at the convenience center again.  Does it still illuminate the test light?

[mamaya3367]

After disconnecting the instrument panel.  The yellow wire contact still shows power and seatbelt light stays on.   

[bd]

    

Unplugging the 18-pin I/P harness connector from the cluster should disconnect the lamp completely from power and ground.  Post pics of the front of the cluster while pointing to the "Seat Belt" lamp.  Now, look at the back of the cluster.  Does the seat belt lamp location have a socket with two protruding wires plugged in from behind?

[mamaya3367]

bd,

I need to make a correction.  I apologize and thank you for your help and patience.

1.  I was measuring the incorrect pin for the yellow wire.  I think I have the correct pin now.  See picture.  With I+ on or off the probe light does not come on for yellow wire.  Seatbelt light on

2.  I removed the Instrument cluster and switched I+ on and the seat belt light stays on.  See picture

3.  I found this black box with a pcb in it.  The seatbelt light yellow and pink/blk wire go there.  If I remove the pcb the seatbelt light turns off.  I'm not able to locate the schematic for the circuit.

[bd]

You're killing me Smalls!

What engine is in the truck?

[mamaya3367]

 hehehe. Sorry

It’s got the 350.

[bd]

I'm not convinced that is the seat belt lamp.  Since you have the cluster out, post pics of the back of the cluster clearly showing the PCB so that it fills the frame, while pointing to where the seat belt lamp plugs in.  I want to trace the circuit pathways on the PCB back to the cluster connector.  Post a pic of the front of the instrument panel while pointing to the location of the seat belt lamp (this is the 2nd time I've asked for this).  Also, post a close-up pic of the 18-pin I/P cluster connector that clearly shows the wires exiting the back of the connector.  I want to see which wire color enters each connector cavity.

[mamaya3367]

Here you go.  Let me know if this will work.

[bd]

There is more to this story.  Is this a California truck?  Does it have a feedback carburetor?

The pics don't reveal enough.  I need to see an unobstructed view with the cluster connector plugged into the back of the cluster that clearly shows the PCB circuit paths from the connector all the way to the seat belt lamp socket.  Post one pic with the seat belt lamp socket plugged into the cluster and another pic from the same perspective with the seat belt socket removed.  I am very interested in the condition of the copper foils that feed power and ground to the lamp.

Answer the questions posed in the pics below.

[mamaya3367]

I purchased the truck in Texas with not much ownership history.  Not sure if there is a carb feedback.  What should I look for?  Attached are pictures showing the connections.  I did the best I could.  Let me know if they will work.

[JohnnyPopper]

Happy now bd?? 

[zieg85]

There is more to this story.  Is this a California truck?  Does it have a feedback carburetor?

  The 2 bbl carb is something I have never seen in the 100+ C10's I've had.  Interesting to me.

[bd]

Look at the image below.  The yellow arrow points to what appears to be a piece of copper foil that is dislodged from the PCB backing and shifted to overlap an adjacent circuit trace, but the pic is low resolution and isn't clear enough to be certain.  I need you to carefully look at the PCB and then describe what you see.  Post more pics if needed, but bump the resolution if you can.

The 2 bbl carb is something I have never seen in the 100+ C10's I've had.  Interesting to me.

Zieg, if you are referring to 2 bbl feedback carbs, they were used dominantly on the 3.8 L V6's in Caballeros and El Caminos.  Virtually all of the V8's with feedback carbs were 4 bbl's - at least in California.

Happy now bd?? 

Gettin' there, but my old eyes are struggling...   

[VileZambonie]

bump the resolution if you can

my old eyes are struggling...   

No kidding. Are you using a motorola flip phone? 

I think you need to send this man a case of beer for this one.