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ECM - Green or Blue Relay Caution

Classification: EC95-014

Reference: NTB95-070

Date: July 5, 1995

GREEN OR BLUE (FUEL PUMP & A/C) RELAY CAUTION

SERVICE INFORMATION

When servicing a customer's vehicle, exercise caution when diagnosing / checking the harness at any green or blue colored relay (Fuel pump & A/C) connector.

SERVICE PROCEDURE

When diagnosing the harness at any green or blue colored relay (Fuel pump & A/C) connector, observe the following pre-cautions to prevent damage to the Engine Control Module (ECM):





1. Note that the schematic on the relay is different than the orientation of the relay terminals in the harness connectors (see diagram):

2. Exercise caution to ensure that the correct terminals are being probed at the relay connector during diagnosing / checking.

NOTE:
Use a circuit tester first to verify the terminals that are supplied with battery voltage. If battery voltage is connected to terminal 2, the ECM will be damaged if the circuit being tested has terminal 2 connected to the ECM.