What Does C1102 Mean?
This code indicates that the ABS control module has detected a malfunction in the acceleration switch circuit, which is used to monitor vehicle acceleration and deceleration for stability control and ABS functions. The acceleration switch (or G-sensor/accelerometer) helps the ABS system determine vehicle dynamics during braking events. The control module has identified an electrical fault such as an open circuit, short circuit, or signal voltage outside the expected range in this sensor circuit.
Common Causes
45%
Faulty acceleration sensor (G-sensor) or internal sensor failure
30%
Damaged, corroded, or loose wiring and connectors in the acceleration sensor circuit
15%
Failed ABS control module or internal circuit board degradation
10%
Poor ground connection at the ABS module or sensor mounting location
Diagnostic Steps
1
Step 1: Perform a visual inspection of the acceleration sensor location (typically mounted near the center console, under seat, or near ABS module) for physical damage, corrosion, or loose mounting. Check connector terminals for corrosion, bent pins, or moisture intrusion.
2
Step 2: Using a digital multimeter, backprobe the acceleration sensor connector and verify supply voltage (typically 5V or 12V reference) and ground circuit continuity with ignition on. Compare readings to manufacturer specifications.
3
Step 3: Measure the sensor signal output voltage while gently tilting the vehicle or sensor (if accessible) to simulate acceleration changes. The voltage should vary smoothly within the expected range (typically 0.5-4.5V). Erratic readings or no change indicates sensor failure.
4
Step 4: Inspect the wiring harness from the sensor to the ABS module for chafing, pinched wires, or damage. Perform continuity tests on all circuit wires with the connector disconnected. Check for shorts to ground or power.
5
Step 5: Verify the ABS module ground connections are clean, tight, and show less than 0.5 ohms resistance to battery negative. Clean and tighten ground points as needed.
6
Step 6: Clear the code and perform a test drive including moderate acceleration and braking events. Monitor live data for acceleration sensor output. If the code returns immediately without physical movement, suspect ABS module internal fault.
Estimated Repair Cost
$150 - $800
Parts + labor, varies by vehicle and location
This code indicates that the ABS control module has detected a malfunction in the acceleration switch circuit, which is used to monitor vehicle acceleration and deceleration for stability control and ABS functions. The acceleration switch (or G-sensor/accelerometer) helps the ABS system determine ve...
The most common cause of C1102 (ABS Acceleration Switch Circuit Failure) is: Faulty acceleration sensor (G-sensor) or internal sensor failure
Typical repair costs for C1102 range from $150 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
The vehicle is generally safe to drive with reduced functionality of ABS, traction control, and stability control systems which may not operate optimally during emergency braking or slippery conditions. Repair should be completed promptly as braking performance may be compromised in adverse conditions, and the ABS warning light will remain illuminated.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to C1102 to identify the root cause.
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Quick Info
Category
Chassis
System
Anti-lock Braking System (ABS) / Vehicle Stability Control
Difficulty
Type
Manufacturer
Recommended Tools
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