B1240 MERCURY - Start Button Mode Indicator Circuit Short
B1240 MERCURY 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 MERCURY 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.
B1240:15 Start Button Mode Indicator Circuit Short to Battery or Open
What is the cost to diagnose the B1240 MERCURY code
Labor: 1.0The cost to diagnose the B1240 MERCURY code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
- Engine Light ON (or Service Engine Soon Warning Light)
B1240 MERCURY MeaningThe 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.
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