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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1997 🢒 DeVille 🢒 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 Setting 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 Val. Position Sw. DTC P1810.
    • The slip is greater than 1504 RPM.
    • The vehicle speed is less than 8 km/h (5 mph).
    • The transmission is in Drive or Reverse.
    • The throttle angle is 65° or greater for 12 seconds.

Action Taken When the DTC Sets

DTC P1814 is stored in the PCM history.

Conditions for Clearing the DTC

A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.

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 Trans 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 A Powertrain On Board Diagnostic (OBD) System Check

2
  1. Install the Scan Tool ®.
  2. With the engine OFF, 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 for reference. Using the Clear Info function will erase the stored Failure Records from the PCM.

  3. Record the DTC Failure Records, then clear the DTC.

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 Trans. 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

In order to verify your repair, perform the following procedure:

  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°.
       - The vehicle speed must be greater than 8 km/h (5 mph).
    • These conditions must persist for more than 12 seconds.
  4. Select Specific DTC. Enter DTC P1814.

Has the test run and passed?

--

System OK

Begin the diagnosis again. Go to Step 1