Desired Engine Speed Signal
Table of contents
P1A05 MERCURY Possible Causes
- Faulty Transmission Control Module (TCM)
- Faulty Powertrain Control Module (PCM)
How do I fix code P1A05 MERCURY?
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’s pins.
Cost of diagnosing the P1A05 MERCURY code
The cost of diagnosing the P1A05 MERCURY 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.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1A05 MERCURY Description
The Transmission Control Module (TCM) continuously monitors the Controlled Area Network (CAN) network for a desired engine speed message from the Powertrain Control Module (PCM). This code is set when the desired engine speed is not within the expected range.