1998 sienna wiring diagram

[zazman]

Where can I find wiring diagram for a '98 sienna XLE? I'm trying to figure out why the EFI fuse keeps blowing and haven't found out where the wires could be getting grounded.
Any help will be greatly appreciated.

[wiswind]

You might try a subscription to alldatadiy.
They have electrical diagrams there.

For my 2003, the EFI fuse goes to the contacts of the EFI relay.......and a branch goes to the ECM (computer) BEFORE the relay.
The fuel injectors get power all the time at 1 lead, and the ECM provides a momentary ground path to energize the injector to spray the fuel.

You might pull the EFI relay out.....and see if the fuse still blows......would eliminate that ECM connecton (pin A).
Not likely that connection, but something past the EFI relay contacts.
Beyond the EFI contacts.....it goes a LOT of places......which is why I recommend the Alldatadiy subscription, so that you can follow the diagram for the 1998.

[zazman]

Hi Wiswind,
Since the fuse blows when taking off it will be difficult to have the relay out and reproduce the problem. What I did was, I bypassed the EFI relay and went straight to the ECM but fused the bypass. With the bypass, there are times on take off when I can feel the car jerk momentarily but the fuse does not get blown. If I insert the EFI fuse with the bypass still in place it still gets blown. I have a partial schematic which shows that after EFI relay contacts, one branch goes to the ECM like you mentioned and the other to another relay that powers the fuel pump.
I have been running the motor without the EFI fuse with just the bypass to see whether the fuse on the bypass would blow but it hasn't. But eventually the motor begins to sputter and quit. This stops after I yank the bypass fuse and put the EFI back.
I'm trying to determine whether the ECM has to do with this or whether there's actually a short somewhere. I've gone as far as I can trying to trace it but without success. I don't know whether a full schematic will be of any help but I'll try.
I also tried an ECM I bought at the junk yard and the results are the same. But then you bever know whether this ECM had the same problem.
What would you suggest I try next?