Very weird electrical issues

[Gazeebo]

Hello everyone:

I currently have a 90 LS400 with a mysterious code 42 (speed sensor 1). I have replaced the speed sensor, instrument cluster and ECU with no avail. Current symptoms are:

Code 42 (O/D light blinking)
Dead speedometer
Dead Odometer
Dead trip meter
Gasoline smell
Very sluggish performance in gear (not in park or neutral)
Erratic shifting

I am seriously thinking it's a wiring issue because car had 2 fuses (GAUGE and CIG) with higher than factory amp rating, I changed them to factory spec fuses and now the battery dies overnight. Any idea what issue this can be? possible wire touching and shorting out?


Thank you very much for any help everyone.

 

[gloverman]

Did you change a two pin or three pin speed sensor?

 

[Gazeebo]

This exact one (3 pin)

 

[gloverman]

The speedo clusters are quite prone to failing. I would be checking the signal is getting to the cluster first and work from there.

 

[Gazeebo]

I replaced my original cluster with another one working and didn't work. How can I test the signal? I'm pretty bad when it comes to wiring and electricity in general.