GMC chervolet camaro 1999 Service Manual page 628

Brakes Antilock Brake System 5-153
OTC C0051 RR Wheel Speed Circuit Range/Performance
C405B
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RR Wheel
0.8WHT C405C
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Speed
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Sensor
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Low
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RRWheel
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Speed Sensor
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Circult Description
The speed sensor used on this vehicle is a single
point magnetic pickup. This sensor produces an AC
signal that the EBTCM uses the frequency from
to calculate the wheel speed. ·
Conditions for Setting the DTC
• The DTC will set if one wheel speed = 0 and the
other WSS are greater than 40 Km/h (25 mph)
for 10 ms, or if the EBTCM detects a short
to ground.
• The DTC will set if during drive off, one wheel
speed= 0, and the other WSS are greater than
12 Km/h (7.5 mph).
Action Taken When the OTC Sets
• A malfunction DTC stores.
• The ABS/TCS disables.
• The amber ABS/TCS indicator(s) turn on.
• The Red BRAKE Warning indicator turns on.
Conditions for Clearing the OTC
• The condition responsible for setting the DTC no
longer exists and the scan tool Clear DTCs
function is used.
• 100 ignition cycles pass with no DTC(s) detected.
Important: After the DTC is cleared by ignition
cycle default, the vehicle must be driven above
12 Km/h (8 mph) for the ABS/TCS indicator(s) to
turn off.
Diagnostic Aids
• 11 is very important that a thorough inspection of
the wiring and connectors be performed. Failure
to carefully and fully inspect wiring and connectors
may result in misdiagnosis, causing part
replacement with reappearance of the malfunction.
213278
• Thoroughly inspect any circuitry that may be
causing the complaint for the following conditions:
- Backed out terminals
- Improper mating
- Broken locks
- Improperly formed or damaged terminals
- Poor terminal-to-wiring connections
- Physical damage to the wiring harness
• The following conditions may cause an intermittent
malfunction:
- A poor connection
- Rubbed-through wire insulation
- A broken wire inside the insulation
• If the customer's comments reflect that the amber
ABS/TCS indicator is on only during moist
environmental conditions (rain, snow, vehicle
wash), inspect all the wheel speed sensor circuitry
for signs of water intrusion. If the DTC is not
current, clear all DTCs and simulate the effects of
water intrusion by using the following procedure:
1. Spray the suspected area with a five
percent saltwater solution.
Add two teaspoons of salt to twelve ounces
of water to make a five percent saltwater
solution.
2. Test drive the vehicle over various road
surfaces (bumps, turns, etc.) above 40 km/h
(25 mph) for at least 30 seconds.
3. If the DTC returns, replace the suspected
harness.
• If an intermittent malfunction exists refer to
Troubleshooting Procedures Cell 4 in Electrical
Diagnosis for further diagnosis.