Description
This function minimizes the loss of the ECT functions when a malfunction occurs in each sensor or solenoid.
Fail-safe
Fail-safe control list:
| Malfunctioning Part | Function |
|---|---|
| Transmission Revolution Sensor (NT) |
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| Transmission Revolution Sensor (NC3) |
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| Transmission Revolution Sensor (SP2) |
|
| Shift solenoid valve SL1, 2, 3, 4, 5 and SR | If the TCM detects a solenoid valve malfunction, it performs fail-safe control. |
| Transmission fluid temperature sensor |
|
| Oil pressure switch | Performs same control when there is a shift solenoid valve SL1 ON malfunction. |
| TCM power supply (voltage is low) |
|
| Knock sensor |
|
| CAN communication |
|
| Shift solenoid valve SLU and SL | Lock up clutch control is prohibited. |
| Shift solenoid valve SLT |
|
Tech Tips
*: In addition to the switching of the shift pattern through the pattern select switch, Artificial Intelligence Shift (AI-SHIFT) control enables the TCM to estimate the road conditions and driver intention in order to automatically select the optimal shift pattern.
Shift Solenoid Valve Normal Operation Chart:
| Gear | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th |
|---|---|---|---|---|---|---|---|---|
| Shift Solenoid Valve SL1 | ON | ON | ON | ON | ON | OFF | OFF | OFF |
| Shift Solenoid Valve SL2 | OFF | OFF | OFF | OFF | ON | ON | ON | ON |
| Shift Solenoid Valve SL3 | OFF | OFF | ON | OFF | OFF | OFF | ON | OFF |
| Shift Solenoid Valve SL4 | OFF | OFF | OFF | ON | OFF | ON | OFF | OFF |
| Shift Solenoid Valve SL5 | OFF | ON | OFF | OFF | OFF | OFF | OFF | ON |
Fail-safe Control Chart:
Tech Tips
*1: Operation of fail-safe is canceled the first time the vehicle stops.
*2: Operation of fail-safe is not canceled for subsequent vehicle stops.
*3: Operation of fail-safe is canceled when a new trip is started.
*4: Operation of fail-safe is not canceled, as a vehicle stop was detected on the previous trip.
*5: For the shift solenoid valve SL1 OFF malfunction, the 3rd trip is started with the fail-safe ON.
Fail-safe operation is performed when the TCM detects a malfunction.
| Gear under normal conditions | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th |
|---|---|---|---|---|---|---|---|---|
| Shift Solenoid Valve SL1: ON malfunction (without fail-safe control) |
1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th |
| Shift Solenoid Valve SL1: Fail-safe control during ON malfunction |
1st | 2nd | 3rd | 4th | 5th | 5th | 5th | 5th |
| Shift Solenoid Valve SL1: OFF malfunction (without fail-safe control) |
N | N | N | N | N | 6th | 7th | 8th |
| Shift Solenoid Valve SL1: Fail-safe control during OFF malfunction |
6th | 6th | 6th | 6th | 6th | 6th | 7th | 8th |
| Shift Solenoid Valve SL1: Fail-safe control during OFF malfunction (from 3rd trip) |
Fixed in 3rd | |||||||
| Shift Solenoid Valve SL2: ON malfunction (without fail-safe control) |
5th | 8th | 7th | 6th | 5th | 6th | 7th | 8th |
| Shift Solenoid Valve SL2: Fail-safe control during ON malfunction |
5th | 5th | 5th | 5th | 5th | 6th | 7th | 8th |
| Shift Solenoid Valve SL2: OFF malfunction (without fail-safe control) |
1st | 2nd | 3rd | 4th | 1st | N | N | N |
| Shift Solenoid Valve SL2: Fail-safe control during OFF malfunction (until vehicle stops) |
Fixed in 7th | |||||||
| Shift Solenoid Valve SL2: Fail-safe control during OFF malfunction*1 |
1st | 2nd | 3rd | 4th | 4th | 4th | 4th | 4th |
| Shift Solenoid Valve SL3: ON malfunction (without fail-safe control) |
3rd | 3rd | 3rd | 3rd | 7th | 7th | 7th | 7th |
| Shift Solenoid Valve SL3: Fail-safe control during ON malfunction (when malfunction is detected in 4th or below) |
Fixed in 3rd | |||||||
| Shift Solenoid Valve SL3: Fail-safe control during ON malfunction (when malfunction is detected in 5th or above) |
Fixed in 7th (If vehicle stops once, fixed in 3rd) |
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| Shift Solenoid Valve SL3: OFF malfunction (without fail-safe control) |
1st | 2nd | 1st | 4th | 5th | 6th | N | 8th |
| Shift Solenoid Valve SL3: Fail-safe control during OFF malfunction (when malfunction is detected in 7th, gear is as shown in chart. If down-shifted to 6th or below once, up-shift to 7th or above is prohibited.) |
1st | 2nd | 4th | 4th | 5th | 6th | 8th | 8th |
| Shift Solenoid Valve SL3: Fail-safe control during OFF malfunction (when malfunction is detected in 6th or below) |
1st | 2nd | 4th | 4th | 5th | 6th | 6th | 6th |
| Shift Solenoid Valve SL4: ON malfunction (without fail-safe control) |
4th | 4th | 3rd | 4th | 6th | 6th | 7th | 6th |
| Shift Solenoid Valve SL4: Fail-safe control during ON malfunction (when malfunction is detected in 4th or below) |
Fixed in 3rd | |||||||
| Shift Solenoid Valve SL4: Fail-safe control during ON malfunction (when malfunction is detected in 5th or above) |
Fixed in 7th (If vehicle stops once, fixed in 3rd) |
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| Shift Solenoid Valve SL4: OFF malfunction (without fail-safe control) |
1st | 2nd | 3rd | 1st | 5th | N | 7th | 8th |
| Shift Solenoid Valve SL4: Fail-safe control during OFF malfunction (when malfunction is detected in 6th, gear is position as shown in chart. If down-shifted to 5th or below once, up-shift to 4th, 6th, 7th, and 8th is prohibited.) |
1st | 2nd | 3rd | 5th | 5th | 7th | 7th | 7th |
| Shift Solenoid Valve SL4: Fail-safe control during OFF malfunction (when malfunction is detected in 4th) |
1st | 2nd | 3rd | 5th | 5th | 5th | 5th | 5th |
| Shift Solenoid Valve SL5: ON malfunction (without fail-safe control) |
2nd | 2nd | 3rd | 4th | 8th | 6th | 7th | 8th |
| Shift Solenoid Valve SL5: Fail-safe control during ON malfunction (when malfunction is detected in 4th or below) |
Fixed in 3rd | |||||||
| Shift Solenoid Valve SL5: Fail-safe control during ON malfunction (when malfunction is detected in 5th or above) |
Fixed in 7th (If vehicle stops once, fixed in 3rd) |
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| Shift Solenoid Valve SL5: OFF malfunction (without fail-safe control) |
1st | 1st | 3rd | 4th | 5th | 6th | 7th | N |
| Shift Solenoid Valve SL5: Fail-safe control during OFF malfunction |
1st | 3rd | 3rd | 4th | 5th | 6th | 7th | 7th |
| Shift Solenoid Valve SR: OFF malfunction (when malfunction occurs in 5th or below) |
1st | 2nd | 3rd | 4th | 1st | 7th | 7th | 7th |
| Shift Solenoid Valve SR: OFF malfunction (when malfunction occurs in 6th or above, or after vehicle shifts to 7th) |
7th | 7th | 7th | 7th | 7th | 7th | 7th | 7th |
| Shift Solenoid Valve SR: Fail-safe control during OFF malfunction (when malfunction is detected in 5th or above) |
Fixed in 7th | |||||||
| Shift Solenoid Valve SR: OFF malfunction (trip is started in malfunctioning state) |
3rd | 3rd | 3rd | 3rd | 7th | 7th | 7th | 7th |
| Shift Solenoid Valve SR: Fail-safe control during OFF malfunction (when malfunction is detected in 4th or below) |
Fixed in 3rd | |||||||
| Shift Solenoid Valve SR: Fail-safe control during OFF malfunction (when malfunction is detected in 5th or above*2) |
Fixed in 7th (If vehicle stops once, fixed in 3rd) |
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Tech Tips
*1: When vehicle is driven after fail-safe detection.
*2: After trip is started in malfunctioning state.
In case of an open or short circuit, the TCM stops sending current to the open or short circuited solenoid.