1991 Chevy Caprice Fault Code 61 - Antilock Brake Pump Rela

Hi Lex,

Thank you for the donation.

The relay is inside the Brake Pressure Modulator. Here are diagnostic procedures.

Code 61 = Pump Motor or relay fault.

CIRCUIT DESCRIPTION
Pump motor returns brake fluid to master cylinder brake circuit at hydraulic modulator during anti -lock braking. During normal braking, pump does not operate. When vehicle begins to move after start-up, EBCM will turn on pump motor and perform a self -check of pump motor and pump motor circuit. Pump motor is an integral part of hydraulic modulator and cannot be serviced separately. Pump motor relay provides power to pump motor. Voltage to motor relay is supplied from circuit No. 1079 (pin No. 17). Motor relay is grounded through circuit No.
854.

Code 61 will set if battery voltage is present at pump motor without pump motor being requested to activate or if battery voltage is not present at pump motor within 60 milliseconds after pump motor has been requested to activate.

NOTE: To avoid misdiagnosis, ensure Red wire to hydraulic modulator is not damaged and is making a clean, tight connection.

TEST DESCRIPTION
Numbers below refer to circled numbers in diagnostic chart.
1 . Checks resistance of relay.
2 . Checks if relay is stuck closed.
3 . Checks for proper switching action in relay.
4 . Checks for open in hydraulic modulator circuit.
5 . Checks for good ground.
6 . Checks resistance of pump motor.
7 . Determines if battery voltage is available to pump motor relay.
8 . Checks for open in circuit No. 854.
9 . Determines if circuit No. 854 is shorted to ground.
10 . Checks for short between circuits No. 854 and 1079.
11 . Checks for open in circuit No. 879.
12 . Determines if circuit No. 879 is shorted to ground.
13 . Checks for short to ground between circuits No. 879 and No. 1079.
14 . Checks for short to voltage on circuit 854 or circuit No. 879.
15 . Checks for internal short to ground within hydraulic modulator.

I only have the location of the brake pressure modulator unit diagram.

Our database does not have the part no nor price list.