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Green or Blue (Type 1M) Relay Caution

Models: All models
Section: Engine Fuel
Classification: EF&EC93-005
Bulletin No.: ITB93-067
Date: December 14, 1993

GREEN OR BLUE (TYPE 1M) RELAY CAUTION

SERVICE INFORMATION

When servicing a customer's vehicle, exercise caution when diagnosing/checking at any green or blue colored relay (type 1M, 1 make-normally open relay) such as the fuel pump, ignition coils, or radiator fans, that is connected to the Engine Control Module (ECM).

SERVICE PROCEDURE

When diagnosing at any green or blue colored relay (type 1M, 1 make-normally open relay), observe the following cautions to prevent damage to the ECM:





1. Note that the schematic on the top of the relay is rotated 90 degrees from the orientation of the relay terminals in the relay connector (see diagram):

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

NOTE:
The relay coil acts as a resistor in this circuit, therefore if terminals 2 or 3 (battery voltage) are connected to terminal 1, the ECM will become damaged if the circuit being tested has terminal 1 connected to the ECM.