I have a 99 camry L4 and I swapped in a instrument cluster from a 98 Es300. Everything works with the exception of the tachometer. I'm guessing it's because of the different signals the v6 one is looking for but I'm having trouble figuring out what I need to do. I'd appreciate any help. The white circuit board is from the L4 and the yellow circuit board the v6. I tried desoldering some of the resistors from the L4 to v6 but not having much luck. I was dumb and forgot to take pictures of the bottom routing but I can take them.

 

Welcome to AAC!

Everything works with the exception of the tachometer.

When you say it doesn't 'work', do you get any reading at all or just the wrong reading?

I tried desoldering some of the resistors from the L4 to v6

Why did you desolder the resistors?

 

The chance that random removal of resistors will give you the results you want is virtually zero.

 

Thanks for the responses.
1. The needle doesn't move at all. I purchased a dakota digital sgi-100bt but the rpms get less accurate the higher the rpms get.
2. Yes I know it was a snowballs chance in hell that swapping resistors would work. Originally I desoldered the eeprom chips on both the 4 and v6 tachs and put in dipsockets so I could easily swap back and forth but im lost now. I can't do it at the moment but I can take more pictures and I'll probably goto the junkyard Saturday and grab a non marred tach from each to start with a clean slate. I'll also take pictures of the underside routing etc

 

1. The needle doesn't move at all.

There are many possible reasons for that.
If you have a multi-meter, as a start you can do continuity checks of the meter coils and also check if there is a supply voltage reaching the coils or the IC.

 

There is voltage outputting from the signal wire. I'm guessing it's because the resistors etc are configured for a v6 with different pulses a second than the 4. Problem is I don't have the knowledge to figure out what it's looking for and how give it the same resistance on the v6 tach to work with the 4cyl tach

 

I'm willing to bet nothing on either tach board will change a thing. Being a stepper motor tach and a computer controlled car most likely the signals for the tach are generated by the ECM.

 

The Tach is most likely calibrated in the ECU with Software adjustments.
The only practical way to fix this is to make sure all the Components are compatible with
the ECU that came with the Engine.

There is a remote chance that a local Hot-Rod-Shop has the Toyota-Tuning-Software that
will facilitate the adjustments You need.
There's an even more remote chance that a Toyota-Dealer can do it for You.
.
.
.

 

If I got close of up pictures of each tach circuit board w/references (ground,12+, signal) would anyone be able to figure out the routing and what the differences are etc?

 

IT'S IN THE SOFTWARE.