Step 
 | Action 
 | Yes 
 | No 
 | 
DEFINITION: This
diagnostic table is designed to diagnose ONLY the components of the DISC brake
system in order to determine if the DISC brake system is operating properly.
You will be directed by the appropriate Symptom Table to go to other brake
system diagnostic tables as appropriate. 
 | 
1 
 | Were you sent here from a Brake
Symptom Table? 
 | Go to 
Step 2
 
 | Go to 
Diagnostic Starting Point - Hydraulic Brakes  
 | 
2 
 | Visually inspect the disc brake pads for the following: 
|     •  | Uneven and/or abnormal wear (edge-to-edge and/or side-to-side) |  
  
|     •  | Evidence of contamination from an external substance |  
  
|     •  | Looseness or damage (including pad hardware) |  
  
Did you find any conditions to indicate a concern with any of the (front
and/or rear) disc brake pads? 
 | Go to 
Step 3
 
 | Go to 
Step 12
 
 | 
3 
 | Are any of the (front and/or rear) disc brake pads contaminated? 
 | Go to 
Step 8
 
 | Go to 
Step 4
 
 | 
4 
 | Are any of the (front
and/or rear) disc brake pads worn unevenly? 
 | Go to 
Step 7
 
 | Go to 
Step 5
 
 | 
5 
 | Are any of the (front and/or rear) disc brake pads and/or pad hardware
loose or damaged? 
 | Go to 
Step 7
      
 | Go to 
Step 6
  
    
 | 
6 
 | 
- Remove and inspect the worn disc brake pads for glazing, looseness,
heat spots or damage.
 
- Replace the worn disc brake pads as a complete axle set. Refer
to 
Front Disc Brake Pads Replacement 
 and/or 
Rear Disc Brake Pads Replacement 
, if equipped, in
Disc Brakes.
 
 
Did you complete the inspection and replacement? 
 | Go to 
Step 12
 
 | -- 
 | 
7 
 | 
Notice: Support the brake caliper with heavy mechanic wire, or equivalent,
whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and
in turn may cause a brake fluid leak.
 - Remove the (front and/or rear) disc brake calipers (as appropriate)
from the mounting brackets and support the calipers. Do NOT disconnect the
hydraulic brake flex hoses from the calipers. Refer to 
Front Brake Caliper Replacement 
 and/or 
Rear Brake Caliper Replacement 
, if equipped, in Disc Brakes.
 
- Inspect the disc brake caliper mounting bracket and the mounting/sliding
hardware for the following conditions:
 
Refer to 
Front Disc Brake Mounting and Hardware Inspection 
 and/or 
Rear Disc Brake Mounting and Hardware Inspection 
, if equipped, in Disc
Brakes. 
| •  | Loose, bent, cracked, or damaged caliper mounting bracket |  
  
| •  | Binding or seized hardware |  
  
| •  | Worn, damaged or missing hardware components |  
  
- Replace components as required.
 
Refer to the following procedures in Disc Brakes, as required: 
- Replace the unevenly-worn, loose or damaged disc brake pads as
a complete axle set. Refer to 
Front Disc Brake Pads Replacement 
 and/or 
Rear Disc Brake Pads Replacement 
, if equipped, in Disc Brakes.
 
 
Did you complete the inspection and replacement? 
 | Go to 
Step 12
 
 | -- 
 | 
8 
 | 
- Inspect the disc brake calipers, brake hoses and brake pipes for
evidence of an external brake fluid leak.
 
- Replace any components found to be leaking brake fluid.
 
Refer to the following procedures as required: 
 
Did you find and correct the source of the leak causing contamination
of the pads? 
 | Go to 
Step 11
 
 | Go to 
Step 9
 
 | 
9
        
 | 
- Inspect the wheel drive shaft outer seals (boots) for damage and
evidence of a grease leak.
 
- Replace any wheel drive shaft seal (boot) that is found to be
leaking grease which may be the source of the contamination to the pads. Refer
 to 
Front Wheel Drive Shaft Outer Joint and Boot Replacement 
 and/or 
Rear Wheel Drive Shaft Outer Joint and Boot Replacement 
, if equipped,  in Wheel Drive
Shafts.
 
 
Did you find and correct the source of the leak causing contamination
of the pads? 
 | Go to 
Step 11
 
 | Go to 
Step 10
 
 | 
10
        
 | 
- Inspect the following systems for damage and evidence of an external
fluid leak.
 
- Replace any components found to be leaking fluid which may be
the source of the contamination to the pads.
 
Refer to the following procedures: 
 
Did you find and correct the source of the leak causing contamination
of the pads? 
 | Go to 
Step 11
 
 | -- 
 | 
11 
 | 
- Clean the remaining disc brake system components to remove any
traces of the contaminant.
 
Notice: Support the brake caliper with heavy mechanic wire, or equivalent,
whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and
in turn may cause a brake fluid leak.
 - Remove the (front and/or rear) disc brake calipers (as appropriate)
from the mounting brackets and support the calipers. Do NOT disconnect the
hydraulic brake flex hoses from the calipers. Refer to 
Front Brake Caliper Replacement 
 and/or 
Rear Brake Caliper Replacement 
, if equipped, in Disc Brakes.
 
- Inspect the disc brake caliper mounting/sliding hardware for the
following conditions:
 
Refer to 
Front Disc Brake Mounting and Hardware Inspection 
 and/or 
Rear Disc Brake Mounting and Hardware Inspection 
, if equipped, in Disc
Brakes. 
| •  | Binding or seized hardware |  
  
| •  | Distorted, worn, damaged or missing hardware components |  
  
- Replace the caliper mounting/sliding hardware components as required.
Refer to 
Front Disc Brake Hardware Replacement 
 and/or 
Rear Disc Brake Hardware Replacement 
, if equipped, in Disc Brakes.
 
- Replace the contaminated disc brake pads as a complete axle set.
Refer to 
Front Disc Brake Pads Replacement 
and/or 
Rear Disc Brake Pads Replacement 
,
if equipped, in Disc Brakes.
 
 
Did you complete the cleaning, inspection and replacement? 
 | Go to 
Step 12
      
 | -- 
 | 
12 
 | 
- Check the thickness of each of the disc brake rotors.
 
Important: Make the following determination AND ANSWER the question INDIVIDUALLY
for EACH rotor.
 - Make a determination for each brake rotor if the rotor can be REFINISHED
and REMAIN ABOVE the minimum requirements.
 
 
Refer to 
Brake Rotor Thickness Measurement 
 in Disc Brakes. 
Does the disc brake rotor meet the minimum requirements for REFINISHING? 
 | Go to 
Step 13
 
 | Go to 
Step 15
    
 | 
13 
 | 
- Inspect each of the disc brake rotors for the following surface
and wear conditions:
 
Refer to 
Brake Rotor Surface and Wear Inspection 
 in Disc Brakes. 
| •  | Braking Surface Conditions |  
  
|    -  | Heavy rust and/or pitting |  
  
|    -  | Cracks and/or heat spots |  
  
|    -  | Excessive blueing discoloration |  
  
| •  | Braking Surface Wear Conditions |  
  
|    -  | Deep or excessive scoring beyond maximum acceptable level |  
  
|    -  | Lateral runout beyond maximum acceptable level |  
  
|    -  | Thickness variation beyond maximum acceptable level |  
  
Important: Make the following determination AND ANSWER the question INDIVIDUALLY
for EACH rotor.
 - Make a determination for each brake rotor if the rotor requires refinishing
based upon the results of the inspection.
 
If the brake rotor exhibits any of the following conditions, it requires
refinishing. 
| •  | Rotor exhibits one or more of the Braking Surface Conditions listed
previously |  
  
| •  | Rotor is beyond the acceptable level in one or more of the Braking
Surface Wear Conditions listed previously |  
  
 
Does the brake rotor require REFINISHING? 
 | Go to 
Step 14
 
 | Go to 
Step 18
 
 | 
14 
 | 
- Refinish the brake rotor. Refer to 
Brake Rotor Refinishing 
 in Disc Brakes.
 
- Inspect the brake rotor thickness. Refer to 
Brake Rotor Thickness Measurement 
 in Disc Brakes.
 
 
Were you able to REFINISH the brake rotor within the minimum requirements? 
 | Go to 
Step 18
 
 | Go to 
Step 17
    
 | 
15 
 | Is the brake
rotor at or below the DISCARD requirements? 
 | Go to 
Step 17
 
 | Go to 
Step 16
   
 | 
16 
 | 
- Inspect each of the disc brake rotors for the following surface
and wear conditions:
 
Refer to 
Brake Rotor Surface and Wear Inspection 
 in Disc Brakes. 
| •  | Braking Surface Conditions |  
  
|    -  | Heavy rust and/or pitting |  
  
|    -  | Cracks and/or heat spots |  
  
|    -  | Excessive blueing discoloration |  
  
| •  | Braking Surface Wear Conditions |  
  
|    -  | Deep or excessive scoring beyond maximum acceptable level |  
  
|    -  | Lateral runout beyond maximum acceptable level |  
  
|    -  | Thickness variation beyond maximum acceptable level |  
  
Important: Make the following determination AND ANSWER the question INDIVIDUALLY
for EACH rotor.
 - Make a determination for each brake rotor if the rotor requires replacement
based upon the results of the inspection.
 
If a brake rotor exhibits any of the following conditions, it requires
replacement. 
| •  | Rotor exhibits one or more of the Braking Surface Conditions listed
previously |  
  
| •  | Rotor is beyond the acceptable level in one or more of the Braking
Surface Wear Conditions listed previously |  
  
 
Does the brake rotor require REPLACEMENT? 
 | Go to 
Step 17
 
 | Go to 
Step 18
 
 | 
17 
 | Replace the brake rotor. Refer to 
Front Brake Rotor Replacement 
 or 
Rear Brake Rotor Replacement 
,  if equipped, in Disc Brakes. 
Did you complete the replacement? 
 | Go to 
Step 18
 
 | -- 
 | 
18 
 | Install or connect components that were removed or disconnected during
diagnosis. 
Did you complete the operation? 
 | Disc Brake System OK 
Return to Symptom Table 
 | -- 
 |