Two problems related to wiring have been reported for the 2004 Toyota Tundra. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Toyota Tundra based on all problems reported for the 2004 Tundra.
Anytime it rains water leaks in behind the dashboard on the passenger side, leaking water through the electrical wiring and into the floorboard of the truck there are lots of wires and a blower motor in this area where fire could cause any number of unsafe conditions. The cause has been narrowed down to one or both of two things. The first is a crack that originates in the seam behind the dash board of these vehicles due to production error. The second is rotting grommet plugs under the windshield wiper cowl. The first being much more severe as it could also cause structural integrity.
Engine would shut off intermittently at any speed, then finally would not start when shut off, dealer replaced fuel pump, same problem happened again in less than 1000 miles, different dealer replaced pump again, same thing happened again within 1000 miles, another dealer replaced wiring harness to pump, in less than 20 miles same thing again, this time the same dealer replaced wiring harness to engine compartment, truck made it back to office, unknown if this fix will work.