Engine-Codes - Generic - B1240

B1240 Code - Start Button Mode Indicator Circuit Short

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

|B1240 code possible causes

  • Faulty Start/Stop Switch Indicator
  • Start/Stop Switch Indicator harness is open or shorted
  • Start/Stop Switch Indicator circuit poor electrical connection
  • Faulty Body Control Module (BCM)

|How is the B1240 code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

|B1240 code tech notes

B1240:11 Start Button Mode Indicator Circuit Short to Ground
B1240:15 Start Button Mode Indicator Circuit Short to Battery or Open

|What is the cost to diagnose the B1240 code

Labor: 1.0

The cost to diagnose the B1240 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

|What are B1240 code possible symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

|What is B1240 code meaning?

The Body Control Module (BCM) uses a Field Effect Transistor (FET) as circuit protection for the start/stop switch indicator and as an electronic switch to turn the start/stop switch indicator on and off. The FET receives fused battery voltage from BCM. When the start/stop switch is pressed a voltage and ground signal are sent to the BCM. When the vehicle enters RUN or START mode, the BCM forward biases the FET which provides voltage to the amber LED in the start/stop switch, illuminating the word ENGINE.

|Need more information with the B1240 code?

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|B1240 code information for specific makes

  • B1240 ACURA Problem In The Mode Control Linkage, Doors, Or Motor Circuit
  • B1240 FORD Start Button Mode Indicator Circuit Short
  • B1240 HONDA Problem In The Mode Control Linkage, Doors, Or Motor Circuit
  • B1240 LINCOLN Start Button Mode Indicator Circuit Short
  • B1240 MERCURY Start Button Mode Indicator Circuit Short

|Need help with a B1240 code?

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