P1840 CADILLAC - Internal Mode Switch 'S' Circuit Low Voltage
P1840 CADILLAC Possible Causes
- Faulty Internal Mode Switch
- Internal Mode Switch harness is open or shorted
- Internal Mode Switch circuit poor electrical connection
First diagnose P1840 CADILLAC code
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 terminals.
Cost of diagnosing the P1840 CADILLAC code
Labor: 1.0The cost of diagnosing the P1840 CADILLAC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
P1840 CADILLAC Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1840 Cadillac DescriptionThe internal mode switch indicates to the Transmission Control Module (TCM) which gear position the vehicle operator has selected. The internal mode switch consists of 5 separate hall effect switches. Each hall effect switch is supplied a 9 V reference circuit and a signal circuit from the TCM. Each signal circuit for each gear selector position will have either a voltage reading of 0.70-0.96 V indicting On or 1.68-2.38 V indicating Off. The voltage values on each internal mode switch circuit will change and are dependent on the position of the gear selector. The state of each internal mode switch A/B/C/P/S signal circuit is displayed on the scan tool.
P1840 CADILLAC More InformationNeed more information on how to fix the P1840 CADILLAC code?
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