GM Testing - Snap-on

Chapter 8 <strong>GM</strong>
<strong>Testing</strong> ABS Systems
8.2.14 Functional Tests—Delco-Moraine III Brake Bleeding
NOTE:
i Operations described in this section are not available on all tool platforms.
A FUNCTIONAL TESTS selection is available for bleeding the Powermaster III electronic
hydraulic control unit (EHCU) solenoids on Delco-Moraine III ABS (Figure 8-70). <strong>GM</strong> manuals
refer to this as “ABS solenoid bleed and checkout test.”
MAIN MENU <strong>GM</strong> ABS
>ABS CODES & DATA
FUNCTIONAL TESTS
CUSTOM SETUP
READ THIS FIRST
(EXIT & RE-ID)
Figure 8-70 MAIN MENU <strong>GM</strong> ABS for Delco-Moraine III
CAUTION:
ä Failure to follow proper brake bleeding procedures may result in improper brake system
operation, or brake system failure.
NOTE:
i This procedure bleeds only the Powermaster III solenoids, not the base brake system or lines.
Refer to <strong>GM</strong> service manuals for additional information.
z To bleed Powermaster III solenoids:
1. Open the Delco-Moraine III Functional Tests menu (Figure 8-71).
SELECT TEST MODE. PRESS Y TO CONTINUE.
>BLEED POWERMASTER SOLENOIDS
Figure 8-71 Delco-Moraine III Functional Tests menu
2. Switch the key on with the engine off.
3. Select BLEED POWERMASTER SOLENOIDS.
The first instructional screen displays (Figure 8-72).
DEPRESS BRAKE PEDAL HALF WAY DURING
ENTIRE PROCEDURE
WARNING: WHEELS MUST NOT ROTATE!
PRESS Y TO CONTINUE.
Figure 8-72 First Delco Moraine III brake bleeding instruction
4. Apply medium pressure to the pedal and press Y.
The next bleeding instruction displays (Figure 8-73).
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