U151E Internal Wiring Harness 2004-2006, used and ready to install. Fits the U151E. Ships fast from the USA.
When a 2004-2006 Toyota Sienna 3.3L, or another V6 Toyota or Lexus with the U151E five-speed, starts throwing several solenoid codes at once, drops into a stuck gear, or shows an ATF temperature code that will not clear, the problem is often not the solenoids at all. It is the internal wiring harness that runs from the case connector to every solenoid inside the pan. This is a used, original Toyota U151E internal harness for 2004-2006 units, pulled and in working condition, for a fraction of what a new dealer harness costs.
The U151E is electronically shifted: the engine computer fires the shift and linear solenoids on the valve body to apply each clutch and brake. All of those signals pass through one sealed connector in the side of the case and then through this harness. In Toyota's repair manual for the U151F (the all-wheel-drive version of the same family), the harness feeds seven solenoid connectors (SL1, SL2, SL3, S4, SR, SLT and DSL) and also carries the ATF temperature sensor circuit, which Toyota tests right at the harness connector between terminals 1 (THO) and 6 (E2). Years of heat cycling in hot ATF make the insulation brittle, and the case connector O-ring hardens and lets fluid wick into the plug.
Read the codes first. One solenoid code usually means one bad solenoid; a cluster of circuit codes, or codes that return right after clearing, points at the common wiring. Unplug the case connector, look for fluid and green corrosion, and measure each solenoid circuit through the connector. Our guide on testing transmission solenoids without a factory scan tool shows how. For the ATF temperature circuit, Toyota's spec is roughly 6.4 k ohms at 68 deg F and 0.2 k ohms at 230 deg F across THO and E2. If a circuit reads open through the harness but the solenoid itself checks good with the pan down, the harness is your part. If the shifts are harsh with no codes at all, read Aisin harsh and delayed shifts before replacing wiring.
This harness comes from a 2004-2006 U151E and was listed for the Toyota Sienna 3.3L in those years. The U151E was also used in V6 Camry, Solara, Highlander, Avalon and Lexus ES330 and RX330 models, but connector layout and harness routing changed across revisions, and the four-cylinder cars use the U241E or U250E, which take a different harness. Before ordering, compare the case connector and the number and color of solenoid plugs on your old harness with the photos, or send us your year and VIN and we will check it. More parts for this family are in our Aisin transmission parts collection.
If a solenoid tested weak while the pan was down, replace it now rather than dropping the pan twice; the U151E solenoid kit covers the set.
| Fits | U151E 2004-2006 |
| Part type | Internal Wiring Harness |
| Condition | Used |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
It came out of a 2004-2006 U151E and was listed for the 2004-2006 Toyota Sienna 3.3L. Other V6 Toyota and Lexus models used the U151E, but match the case connector and solenoid plug count to your old harness or send us your VIN before ordering.
No. Four-cylinder models use the U241E or U250E transaxle, which has a different internal harness.
In Toyota's design the temperature sensor circuit runs through this harness and the sensor mounts with a lock plate and bolt. Compare the listing photos with your old part to see exactly what is attached.
Multiple solenoid open or short codes at the same time, codes that return immediately after clearing, or ATF temperature codes P0710, P0712 or P0713 along with solenoid codes usually point at common wiring or the case connector.
Refill with Toyota Genuine ATF WS and check the level at operating temperature. Then perform the A/T reset memory procedure so the computer relearns shift pressures.
It is a used original Toyota harness in working condition, a lower-cost alternative to a new dealer harness.
