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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 Transmission/Transaxle 🢒 Automatic Transaxle - 4T80-E 🢒 DTC P1814

Object Number: 20680 Size: LF
Master Electrical Component List
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.

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. DTC P1814 is a type C DTC.

Conditions for Running the DTC
    • No TP DTCs P0121, P0122 or P0123.
    • No VSS DTCs P0502 or P0503.
    • No IMS DTCs P1820, P1822, P1823 or P1825.
    • The transmission is not in PARK or NEUTRAL.
    • The vehicle speed is 8 k/m (5 mph) or less.
    • The TCC slip speed is 1,500 RPM or greater.

Conditions for Setting the DTC

The TP angle is 79 percent or greater for 12 seconds.

Action Taken When the DTC Sets
    • The PCM does not illuminate the malfunction indicator lamp (MIL).
    • The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records.
    • The PCM stores DTC P1814 in PCM history.

Conditions for Clearing the DTC
    • A scan tool can clear the DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes.

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

DTC P1814

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls in Engine Controls

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.

    3. Important: Before clearing the DTC, 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 DTC Failure Records.
  4. Clear the DTC.
  5. Review the stored P1814 Failure Records and select Fail Counter.

Is the P1814 fail counter greater than 1?

--

Go to Step 4

Go to Step 3

3

Did you perform the Transmission Fluid Checking Procedure?

--

Go to Step 5

Go to Transmission Fluid Check

4

  1. Change the AT fluid and filter.

    2. Refer to Fluid Filter Replacement.

  2. Inspect the AT fluid for correct level.
  3. Add new fluid as necessary.
  4. Use the scan tool in order to reset the oil life monitor to 100%.

Did you complete the above procedures?

--

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 vehicle speed must be 8 km/h (5 mph) or less.
       - The TCC slip speed must be 1,500 RPM or less.
       - The TP angle must be 79% or less.
    • These conditions must be true for 3 seconds.
  4. Select Specific DTC.
  5. Enter DTC P1814.

Has the test run and passed?

--

System OK

Go to Step 1