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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Transmission/Transaxle 🢒 Automatic Transaxle - 4T80-E 🢒 DTC P1814 Torque Converter Overstressed

Object Number: 20680 Size: LF
Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice

Circuit Description

This diagnostic test checks for unusually high throttle angle and low vehicle speed when the transmission is in DRIVE or REVERSE. The primary purpose of this DTC is to record the Failure Record Data, because this condition could damage the powertrain or create an unsafe condition. DTC P1814 is a Type D DTC.

If the PCM detects an unusually high throttle angle and low vehicle speed when the transmission is in DRIVE or REVERSE, then DTC P1814 sets.

Conditions for Running the DTC
    • No TP DTCs P0121, P0122, or P0123.
    • No VSS DTCs P0502 or P0503.
    • No A/T ISS DTCs P0716 or P0717.
    • No TFP manual valve position switch DTC P1810.

Conditions for Setting the DTC

All of the following conditions are true for 12 seconds.

    • The transmission is in DRIVE or REVERSE.
    • The throttle angle is 65 degrees or greater.
    • The slip is greater than 1504 RPM.
    • The vehicle speed is less than 8 km/h (5 mph).

Action Taken When the DTC Sets
    • The PCM does not illuminate the malfunction indicator lamp (MIL).
    • The PCM stores DTC P1814 in PCM history.

Conditions for Clearing the DTC
    • A scan tool can clear the DTC from PCM history.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.

Diagnostic Aids

A simultaneous acceleration and application of the brakes may cause DTC P1814 to occur.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step inspects the failure records for DTC P1814 occurrences.

    2.

  2. Important: Reset Transmission Oil Life when you replace the fluid and the filter.

    This step replaces the fluid and the filter. If DTC P1814 occurs more than once in the failure records, severe TCC damage may have occurred.

DTC P1814 Torque Converter Overstress

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Install the Scan Tool .
  2. Turn the ignition switch to the RUN position.

    3. Important: Before clearing the DTCs, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the PCM.

  3. Record the Failure Records.
  4. Clear the DTCs.

Does DTC P1814 failure counter indicate more than 1?

--

Go to Step 4

Go to Step 3

3

Inspect the transmission fluid level and color.

Refer to Transmission Fluid Check .

Is the inspection complete?

--

Go to Step 5

--

4

Important: Reset Transmission Oil Life when you replace the fluid and the filter.

Replace the transmission fluid and the scavenge screens.

Is the repair complete?

--

Go to Step 5

--

5

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Operate the vehicle under the following conditions:
    4. • Road test the vehicle with the gear select lever in D4.
       - The TCC slip must be less than 1504 RPM.
       - The TP Angle must be less than 65 degrees.
       - The vehicle speed must be greater than 8 km/h (5 mph).
    • These conditions must be true for greater than 12 seconds.
  4. Select Specific DTC. Enter DTC P1814.

Has the test run and passed?

--

System OK

Go to Step 1