Various Non-Working Instrument Cluster Warnings - Not bulbs

[masonbarnard]

Hey,
So I bought a '94 Land Cruiser a couple of months ago, and various warning lights do not illuminate during key-on engine-off. Most notably, the check engine light.

I pulled the cluster, replaced all the bulbs, and the same thing... No fix. I then cleaned all the contact points and pried them up a bit so they make a more forceful connection... No fix. I put the known working bulbs in the non-working spots, and they still did not work... (it's not the bulbs)... I then checked all the grounds and made sure there was nothing unplugged or tampered with... Found nothing.

Any ideas on where to start next?

 

[voodu3]

Check the ecu. There are testing procedures in the FSM. Or if you can locate a known good one swap it and see if the CEL lights up.

 

[jonheld]

On a 94 (OBD1):
The CEL gets +12 from the GAUGE fuse and is grounded by ECU connector E7-pin 4 to illuminate the bulb.
You should be able to probe CHECK CONNECTOR pin 2 to verify.

All the information is in the Toyota FSM and EWD that you can download from the resources section.

 

[masonbarnard]

So I jumped TE1 to E1, it did not flash codes. I jumped W to E1, it did not illuminate the CEL. I confirmed there is 12v at the CEL bulb socket at the cluster and manually grounded the socket to prove that it could illumate.

I then measured 12v at W terminal of diag port, and confirmed E1 has continuity to the battery ground. There was no continuity between W cluster pin and diag port W terminal, which I believe proves there is a OPEN somewhere.

Searched high and low for anything that looked off... Nothing did. So I decided to run a bypass wire from the cluster W pin to the diagnostic port W - This finally illuminated the check engine light via key on engine off... was excited to see that.

So now im running it with a wire... Might just keep it that way... Assuming that a real check engine light (not key on engine off) would illuminate with the set up i currently have?