Optra Brake Pressure Modulator Replacement
Chevrolet Optra Brake Pressure Modulator ReplacementWarning
Brake fluid may irritate eyes and skin. In case of contact, take the following actions:
Eye contact-rinse thoroughly with water.
Skin contact-wash with soap and water.
If ingested-consult a physician immediately.
Removal Procedure
1. Drain the brake fluid from the brake system.
2. Turn the ignition switch to the OFF position.
3. Drain the engine coolant to below the level of the surge tank.
4. Loosen the return hose clamp and disconnect the return hose from the top of the surge tank.
5. Loosen the throttle body hose clamp and disconnect the throttle body hose from the top of the surge tank.
6. Loosen the feed hose clamp and disconnect the feed hose from the bottom of the surge tank.
7. Remove the surge tank attaching bolt.
8. Remove the surge tank from the support mount.
Warning
Wear safety glasses in order to avoid eye damage.
9. Clean the brake modulator assembly pipe fitting areas of any accumulated dirt and foreign material.
10. Disconnect the electrical connector from the electronic brake control module (EBCM).
11. Place a shop towel under the brake modulator assembly to catch any brake fluid loss.
Note
Prior to disconnecting the brake pipes from the antilock brake system (ABS) modulator assembly, note the locations of the brake pipes to the valve assembly, to aid during installation.
12. Disconnect the brake pipe fitting nuts from the brake pressure modulator valve (BPMV).
13. Cap the brake pipe ends to prevent brake fluid loss and contamination.
14. Plug the modulator brake pipe openings to prevent brake fluid loss and contamination.
15. Remove the mounting bracket bolt and nuts from the body panel.
16. Remove the brake modulator assembly to the mounting bracket damping bolts.
17. Remove the ABS module from bracket.
18. Remove the mounting pins from ABS module.
19. Remove the HCU from EBCM. (ABS: 3 bolts, ESC: 4 bolts).
20. Install new HCU onto EBCM. Tighten the mounting bolts to 1.8 Nm (16 lb-in).
21. Install the mounting pins from ABS module. Tighten mounting pins: 8 Nm (6 lb-ft).
22. Install the brake modulator assembly to the modulator bracket.Tighten mounting bolts: 8 Nm (6 lb-ft).
23. Install the damping bolts to the brake modulator assembly. Tighten the damping bolts to the brake modulator assembly to 11 N.m (8 lb-ft).
24. Install the brake modulator assembly with the mounting bracket attached to the body panel. Tighten the mounting bracket bolt and nuts to 22 Nm (16 lb-ft).
25. Remove the caps from the master cylinder brake pipe ends.
26. Remove the plugs from the master cylinder ports on the modulator assembly.
27. Connect the master cylinder brake pipes to the modulator assembly, in the same location as removed.
28. Tighten the brake pipe fittings nuts. Tighten the fitting nuts to 16 Nm (12 lb-ft).
29. Connect the electrical connector to the EBCM.
Note
Refill coolant in the reservior tank properly. It may need about one liter.
30. Install the engine coolant reservior tank.
Note
Fill the master cylinder reservoir with brake fluid. Ensure the master cylinder is at least 1/2 full of fluid during the brake bleeding operation. Fill brake system with Delco Supreme 11 Brake Fluid (P/N 19299818 USA, P/N 19299819 Canada).
31. Bleed the brake system. Refer to Hydraulic Brake System Bleeding in SI.