Technical Procedure

1. With the ignition in the "OFF" position, open hood and disconnect negative battery cable.

2. Remove instrument panel right sound insulator. Remove glove box, if required.

3. Loosen 10mm nut(s) for Electronic Control Module (ECM) to mounting bracket.

4. Disconnect electrical connectors and remove ECM. See Section 8C of appropriate model Chassis Service Manual for illustration and removal instructions.

5. Remove PROM access cover.

FIGURE 1:

6. Remove PROM assembly using the rocker-type PROM removal tool. See Figure 1

NOTICE: Using the rocker-type PROM removal tool, engage one end of the PROM carrier with the hook end of the tool. Press on the vertical bar end of the tool and rock the engaged end of the PROM carrier up as far as possible. Engage the opposite end of the PROM carrier in the same manner and rack this end up as far as possible. Repeat this process until the PROM carrier and PROM are free of the PROM socket. The PROM carrier with PROM in it should lift off of the PROM socket easily. PROM carrier should only be removed by using the pictured PROM removal tool. Other methods could cause damage to the PROM or PROM socket.

FIGURE 2:

7. Install new PROM assembly in ECM. On the Electra/Park Avenue, install new PROM based on old PROM Code or Scanner PROM I.D. per the Parts Information section.

NOTICE: Small notch of PROM carrier should be aligned with small notch in ECM socket. Press on PROM carrier until it is firmly seated in the socket. Do not press on PROM, only on the carrier (See Figure 2).

8. Reverse Steps 5 to 1 to reinstall ECM.

9. Start the engine and observe check engine light. If it does not go out, the PROM was installed backwards and is now damaged; a new PROM will have to be installed in the correct orientation.

10. Install Campaign Identification Label. Advise owner that battery has been disconnected and clock and radio stations may need to be reset.