2021-2024 Hyundai Santa Fe / Tucson DTC U028700 EOP

Hyundai has released Technical Service Bulletin (TSB) 26-AT-002H to address an issue affecting certain 2021-2024 Santa Fe and Tucson vehicles. This bulletin specifically targets vehicles equipped with a 2.5L GDI engine and an 8-speed automatic transmission that may log diagnostic trouble code (DTC) U028700.

The TSB outlines a procedure for replacing the Electric Oil Pump (EOP) when this specific DTC is present. Owners of affected vehicles, including the Hyundai Tucson DTC U028700, should be aware of this service action.

Important Warnings and Owner Information

Hyundai emphasizes that this field action requires a confirmed customer concern and a verified symptom related to the TSB before any repair work can proceed. Claims submitted without meeting these justification requirements may be subject to debit.

• Warranty Coverage: The 10-year/100,000-mile Powertrain Limited Warranty for original owners and 5-year/60,000-mile New Vehicle Limited Warranty (NVLW) for subsequent owners apply to the parts and repair procedures outlined in this TSB. Dealers must ensure parts are within applicable warranty coverage before beginning work.
• Proper Torque: Technicians are advised that applying the recommended torque to all fasteners is crucial to prevent potential issues after the service procedure.
• DTC Justification: This TSB includes repair justification via automatically uploaded DTCs through the GDS e-Report at the time of diagnosis. DTC history can be reviewed to ensure adherence to the Digital Documentation Policy.

Symptoms You Might Notice

The primary symptom associated with DTC U028700 is that the "Idle Stop & Go (ISG) system" may become inoperative. This means your vehicle's engine might not automatically shut off and restart as expected when stopped in traffic.

Fault Codes / DTCs

This TSB specifically addresses Diagnostic Trouble Code (DTC) U028700. The description for this code is "Lost Communication With Trans Fluid Pump Module." It's important to note that DTC U028700 does not illuminate a warning light in the instrument cluster, but it is stored in the transmission control unit.

Diagnosis and Trigger Conditions

To diagnose this issue, a technician will use the Global Diagnostic System (GDS) to perform a "Fault Code Searching" procedure in the Automatic Transmission (AT) system. The TSB applies only if DTC U028700 is found in an "Active" status. If the DTC is not active, or if other DTCs are present, this specific TSB does not apply, and normal diagnostic procedures should be followed.

Repair Procedure Summary

The repair procedure outlined in TSB 26-AT-002H involves replacing the Electric Oil Pump (EOP) assembly. Here's a summary of the steps:

1. DTC Confirmation: Confirm DTC U028700 is active using GDS.
2. Battery Disconnection: Disconnect the negative (-) battery cable.
3. Vehicle Preparation: Raise the vehicle, ensuring lift blocks are properly seated on designated support points to avoid damage.
4. Under Cover Removal: Remove the engine room under cover as per the shop manual instructions.
5. EOP Disconnection: Disconnect the electric oil pump (EOP) connector.
6. EOP Removal: Remove the four bolts securing the EOP to the transmission and then remove the EOP.
7. O-Ring and EOP Replacement: Replace the two O-rings and install the new EOP in the reverse order of removal.
8. EOP Connection: Connect the electric oil pump (EOP) connector.
9. ATF Addition: Add 24 oz. (0.7 liters) of the proper Automatic Transmission Fluid (ATF) to the injection hole before starting the engine. Check the ATF level and inspect for leaks.
10. Reassembly: Reinstall all components in the reverse order of removal.
11. DTC Clearance: Using GDS, erase the DTC history and perform a fault code search to confirm that DTC U028700 does not reset.

Required Tools or Parts

To perform this repair, the following parts are specified:

• Pump Assy - Electric Oil: Part Number 46110-2F600QQH (Applies to 8AT Transmission Only)
• ATF SP4-M1: Part Number 00232-19107 (Quantity: 1 Quart)
• O-Ring: Part Number 45263-3B000 (Quantity: 1)
• O-Ring: Part Number 45262-3B100 (Quantity: 1)
• Eye Bolt Assy: Part Number 45284-4G800 (Quantity: 1)

Owner Action

If you own a 2021-2024 Hyundai Santa Fe or Tucson and are experiencing an inoperative Idle Stop & Go system, especially if you suspect a Hyundai Tucson DTC U028700, you should contact your authorized Hyundai dealer. Inform them of the symptoms and mention TSB 26-AT-002H. The dealer will diagnose the issue and perform the necessary Electric Oil Pump replacement if the conditions for the TSB are met. This repair is typically covered under the vehicle's powertrain warranty, provided the vehicle meets the mileage and ownership criteria.

Warranty Information

Claims for this service should be submitted as a "Campaign" type. The repair time is estimated at 0.9 hours. If any parts not covered by this TSB are found to need replacement during the procedure, and they are still under warranty, the dealer may submit a separate claim. For out-of-warranty parts, a Prior Authorization (PA) Request for goodwill consideration may be submitted on a case-by-case basis.

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Source: NHTSA ID: 11028968