How to properly On-Board FLASH reprogram Cadillac ECC’s

Application: 1996-99 Cadillac’s (all models), 2000-01 Cadillac Seville, and Deville.

The following steps are necessary to allow On-Board FLASH reprogramming of the ECC on certain Cadillac models:

Caution: The power feed to the ECC must be disconnected before reprogramming.

Before disconnecting the power, the ignition key must be placed in the LOCK position for a minimum of 30 seconds. This process allows the ECC to store values for the transaxle fluid life, transaxle shift adaptive and throttle position learned values into the EEPROM section of the ECC. Failure to wait the specified time (30 seconds) will result in an EEPROM reset and loss of transaxle fluid life info and a reset value back to 0.

 

To FLASH reprogram Cadillacs from model years 1996-99 perform the following process:

• Locate the ECC. With the ignition in the LOCK position, wait 30 seconds (see above), then carefully remove the clear connector on the ECC.
• Reprogram the ECC as outlined in the vehicle service’s manual.

To FLASH reprogram Cadillacs from model years 2000-01 Seville and

 

Deville models (VIN K):

• Place the ignition key in the LOCK position, wait 30 seconds, then pull instrument panel cluster (IPC) fuse #7 (located in underhood panel) and ignition fuse #12 (located under back seat). Pulling the fuses indicated will allow FLASH reprogramming of these applications.
• Reprogram the ECC as outlined in the vehicle service’s manual.

NOTE: Maintain 12.5 to 13 volts during the reprogramming process. Failure to do so will result in an ECC failure! Refer to your vehicle’s service manual for specific service procedures. The ignition switch supplies power to the ECC in all key positions except LOCK. To avoid ECC damage when removing or installing any

ECC, always put the switch in LOCK.