Engine-Codes - Generic - B1840

B1840 Code - Driver Seat Lumbar Up Switch Circuit

- Code Popularity: 7,761 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC B1840?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Driver Seat Adjuster Switch
  • Driver Seat Adjuster Switch harness is open or shorted
  • Driver Seat Adjuster Switch circuit poor electrical connection
  • Faulty Seat Memory Control Module

Code Tech Notes





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How to Fix the DTC B1840?

Check 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 pins.

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What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the B1840 code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

What are Code Possible Symptoms?

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

What Does the B1840 Code Mean?

The Seat Memory Control Module supplies a reference voltage to each signal circuit of the Driver Seat Adjuster Switch. When the power seat or lumbar switches are pressed, the appropriate signal circuit from the Seat Memory Control Module is pulled low through the switch contacts indicating the power seat command. The Seat Memory Control Module then commands the driver seat or lumbar to move in response to the switch signals. The Diagnostic Trouble Code (DTC) will be set when there is a short to ground on a switch signal circuit.

B1840 Code - Driver Seat Lumbar Up Switch Circuit

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Code B1840 Information for Specific Makes

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