Kia Optima DL3 Quiz
Automatic Transmission

Underdrive Brake Control Solenoid Valve (UD/B_VFS)

In this manual: Automatic Transmission
General Information — 8Advanced Driver Assistance System (ADAS) — 21Maintenance — 27Engine Mechanical System — 45Engine Electrical System — 11Emission Control System — 11Engine Control System/Fuel System — 25Automatic Transmission — 20Drive Shaft and Axle — 7Suspension System — 22Steering — 7Restraints — 11Brake System — 22Body (Interior and Exterior) — 116Body Electrical System — 90Heating, Ventilation, and Air Conditioning — 32
18steps
~108min
4/5difficulty
02040608010043.132N·mlb·ft
Tightening torque found on this page
Done 0 of 18

Specifications

Specification

Item Specification
Control Type N/H (Normally High)
Control Pressure (kPa (kgf/cm², psi)) 0–1 569,06 (0–16, 0–227,57)
Current (mA) 0 - 1100
Coil Resistance (Ω) 5,3 ± 0,3

Description and Operation

Description

  • The low gear brake control solenoid valve is a variable force solenoid (VFS) type.

  • When the TCM supplies current to the solenoid valve, the hydraulic pressure of the low gear brake is controlled by the solenoid valve.

Low Gear Brake Control Solenoid Valve Circuit

UD/B_VFS
N·m
N, P ●
1
2
3
4
5 ●
6 ●
R ●

● : Connection status

Components and Component Location

Component Location

1. Valve Body Cover 8. On/Off Solenoid Valve SS-A
2. Valve Body Gasket 9. Torque Converter Control Solenoid Valve
3. Main Suspension 10. Line Pressure Control Solenoid Valve
4. 2/6 Brake Control Solenoid Valve 11. Support Bracket
5. 35R Clutch Control Solenoid Valve 12. Support Bracket
6. Low Gear Brake Control Solenoid Valve
7. Overdrive Clutch Control Solenoid Valve

Repair Procedures

Inspection

  1. The automatic transmission system can be diagnosed for malfunctions more quickly using the Kia Diagnostic System (KDS).

    KDS provides the following information.

    1. Self-diagnosis: Checks and displays diagnostic trouble codes (DTC).

    2. Data list: Checks the input/output values of the system.

    3. Active test: Checks the operating condition of the system.

    4. Additional functions: System option control, zero point adjustment, and other functions.

Component Inspection

  1. Turn the ignition off.

  2. Remove the air cleaner assembly.

    (Refer to Engine Mechanical System - "Air Cleaner")

  3. Remove the battery and battery tray.

    (Refer to Engine Electrical System - Battery)

  4. Disconnect the solenoid valve connector (A).

  5. Measure the resistance between the power terminal (5) and the signal terminal (16).

    Specification: 5.3 ± 0.3 Ω

Removal

  1. Remove the under cover.

    (Refer to Engine Mechanical System - "Engine Room Cover")

  2. Remove the ATF drain plug (A), allow the fluid to drain, and then reinstall the drain plug.

    Tightening torque: 33.3–43 N·m

  3. Remove the air duct and air cleaner assembly.

    (Refer to Engine Mechanical System - "Air Cleaner")

  4. Remove the retaining clamp (A) and the breather hose (B).

    Tightening torque: 9.8–11.8 N·m

  5. Disconnect the ATF cooler hose (A).

  6. Raise the vehicle after loosening the upper valve body cover bolts.

  7. Remove the valve body cover (A) by loosening the bolts.

    Tightening torque: 11.8–13.7 N·m

  8. Remove the main harness assembly (A) after removing the bolts.

    Tightening torque: 9.8–11.8 N·m

  9. Remove the solenoid valve support bracket (A) after loosening the bolts.

    Tightening torque: 9.8–11.8 N·m

  10. Remove the solenoid valve retaining pin (A) and loosen the valve body mounting bolt (B).

    Tightening torque: 9.8–11.8 N·m

  11. Remove the low gear brake control solenoid valve (A).

Installation

  1. Install in the reverse order of removal.

  2. After installation, perform the procedures described below.

    1. Fill the automatic transmission with fluid.

      (Refer to Hydraulic System - "Fluid")

    2. Erase the diagnostic trouble codes (DTCs) using the KDS. Disconnecting the negative battery terminal will not erase DTCs. Always use the KDS to erase trouble codes.

    3. Reset the automatic transmission adaptive values using the KDS.

    4. Perform the oil pressure characteristic entry procedure using the KDS.

      (Refer to Hydraulic System - "Oil Pressure Characteristic Entry")

    5. Check for coolant or fluid leaks from the hose connections while the engine is running.

    6. Perform the TCM adaptive value learning procedure.

      (Refer to "Automatic Transmission Control System - Adjustment")

Test yourself

A quick Kia Optima DL3 quiz: every answer comes with an explanation and a link to the manual page.