AutoCodes.com | All About OBDII Engine Codes
AutoCodes - Generic - C1100

C1100 Code - ABS Pump Switch Circuit Failure

- Code Popularity: 35,710 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents
Share on Facebook   Share on Twitter   Share on Linkedin

What are the Possible Causes of the DTC C1100?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • ABS Pump Switch / Wiring intermittently open/shorted
  • Faulty / intermittent connection at the Anti-Lock Brake Control Module (ABCM or EBCM)
  • Faulty Anti-Lock Brake Control Module
⚠ Does your Car have Safety Recalls? → Check here

How to Fix the DTC C1100?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes

This is typically an electrical wiring connection issue the ABS Control Module monitors for the manufacturer.
It can occur if: The pressure switch/wiring itself is bad.

Search for C1100 Questions and Answers: Search here →

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the C1100 code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

When is the Code Detected?

If the ABCM \ EBCM is unable to test the ABS pump switch any time after the ignition switch is first turned to the “Run” position, code C1100 is set in memory.

What are Code Possible Symptoms?

  • Anti-Lock Brake System (ABS) Warning Light ON
  • Engine Light ON (or Service Engine Soon Warning Light)

Code C1100 Description

When the driver stops too fast, and one or more wheels begin to lock up, the ABS system takes over. It sees the wheel or wheels slowing down too rapidly by way of wheel speed sensors. When this happens, it shuts off brake fluid to the wheel with the inlet valve/coil, and releases the pressure with an outlet valve/coil. The ABS pump is what replenishes the brake fluid, and the ABS Pump Switch informs the ABS control module when the pump is running/turns on the pump depending upon manufacturer’s application. The ABS pump switch is typically found on vehicles with 4 Wheel Anti-Lock Brakes. The ABS system checks to be sure that the switch electrical circuit is ok every time the key is turned on and the ABS module is powered up. If there is a problem with the wiring to the switch or the switch itself, the ABS module will communicate over a data bus to the instrument cluster to turn on the amber Anti-Lock Light and the Red Brake Warning Light, and ABS will be disabled. In this case, the module has checked the ABS pump switch wiring and found the circuit has an electrical problem. This sets a C1100 in memory.

OBDII Code C1100 - ABS Pump Switch Circuit Failure - AutoCodes.com
C1100 Code - ABS Pump Switch Circuit Failure

Need More Information on the Code?

Need more information on how to fix the C1100 code? Get Access to Factory Service Manuals

Information for Specific Makes

Need Help with the Code?

Get the C1100 code diagnosed by a professional: Find a repair shop in your area

Code C1100 comments

Help us improve AutoCodes.com. Leave a comment below or tell us if the information above helps you fix the code. What are the symptoms on your vehicle for the C1100 code? Have you replaced any parts?
Any information is appreciated. Thanks