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2X
05/26/2018, 02:24 PM
Hi,

I am trouble shooting an electrical issue that may be related to when the TOD system is active.

The idea is to disconnect the TOD under the passenger seat. then see if the electrical issue stops occurring.

My #23 fuse in the driver side fuse box... wants to keep blowing out..

My mechanic says he cannot find the cause... and next to look at possibly a short in the components connected to #23...

TOD is not connected to #23... but the fuse failure seems to happen with TOD engaging...

The idea is to take TOD off line as a test... before going back to shop for a deeper dive into the electronics...

So, what happens if TOD is disconnected?

Can driving function without damage to drivetrain?

Which of the two connections on the TOD control unit does one unplug?

One or both?

Any assistance is appreciated.

I have searched through the archives... with hit or miss info found..

Thanks,

Ro...

Thelgord
05/27/2018, 08:10 AM
Looking at the wiring diagrams in the Shop Manual, fuse 23 from that fuse box is called CB-3, or CB-03 depending on the chart you are looking at. It is the fuse for the main engine ECU (Under center lower dash) & The coil packs.

CB-16 (Fuse Locatin 36) is the power for the TOD Computer. CB-04 (Fuse location 24) is for the TOD lights on the dash. All of these locations are supplied by the ignition switch.

Being that the same fuse is for the ECU and the coil packs, and the fuse blows when TOD engages (IE: you are giving it throttle) I would look at the wiring to the coil packs.

However, to your question about disengaging the TOD computer. There are mixed messages. SOme say you can snap a front half shaft. It has happened in at least one instance, however the details of surrounding it are incomplete and lack details. Keep in mind that the wheels are still going to spin the front axle, and the front driveline, and the 4WD side of the transfer case, even with the TOD computer off, while the vehicle is moving. Also keep in mind the age of the vehicle.

However, others have disable the TOD computer without any ill effects reported. With the lack of imperial data, I would say your odds of breaking something are around 50/50.

Good luck in your hunt. Electrical is such a PITA.

MSHardeman
05/29/2018, 10:31 AM
Maybe try a TOD disconnect switch:

http://www.vehicross.info/showthread.php/14787-Easy-TOD-off-switch!!?highlight=tod%20blue%20wire

I know someone else did a write-up on a more involved disconnect switch, but I can't seem to find it right now.

2X
05/29/2018, 10:36 PM
I’m thinking the issue may be the fuel pump relay coil... heating up.,. One mechanic put this at top of list...

Will try replacing relay...

Thanks

Nikad92397
06/08/2018, 07:22 AM
If you do try disconnecting the TOD computer, also add manual locking ( $100.00 new or very cheap at a pick/pull) hubs. I run this way 40,000+ miles.. That will solve anyother problems with your driveline that might occur. It the fuse blows when the TOD kicks in you might look by the transfer case. The wires run dangerously close to the muffler (another common problem) and might be burned / shorting out. You can disconnect the computer for a few test runs with no damage. Avoid tight turns. Some have had driveline failures but I have never heard of it happening instantly.