Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble reading important information from a special memory chip that helps control the transmission.
The Transmission Control Module (TCM) uses EEPROM to store data that is critical for its operation. A reading error indicates that the TCM is unable to correctly access this data.
The P179A code indicates a fault in reading the EEPROM (Electrically Erasable Programmable Read-Only Memory) within the Transmission Control Module. This memory stores essential calibration and operational data. If the TCM cannot read this data, it may lead to improper transmission operation.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may enter 'limp' mode
• Faulty Transmission Control Module
• Corrupted EEPROM data
• Wiring issues or poor connections to the TCM
EEPROM: Electrically Erasable Programmable Read-Only Memory, a type of memory used to store important data.
TCM: Transmission Control Module, the computer that controls the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the TCM.
• Check for any software updates or reprogramming needs for the TCM.
• Repair or replace faulty wiring or connectors.
• Reprogram or update the TCM software.
• Replace the Transmission Control Module if necessary.
• OBD-II Scanner
• Multimeter
• Screwdrivers and socket set
$300 - $1,200
Moderate
• Volkswagen Jetta
• Audi A4
• Skoda Octavia
• Regularly update vehicle software.
• Ensure proper maintenance of electrical connections.
• Avoid aftermarket modifications that may affect the TCM.
Transmission Control Issue
• Avoid driving at high speeds until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
• Do not ignore the warning light as it may lead to further damage.
Check with the vehicle manufacturer for warranty coverage on TCM issues.
This code has been associated with issues in vehicles with complex electronic transmission systems.
High – Can affect vehicle drivability and lead to further transmission damage.
Driving with a faulty transmission control can be unsafe and may lead to further mechanical damage.
• Vehicle at operating temperature
• Transmission in neutral or park
The Transmission Control Module is typically located near the transmission or within the engine compartment.
Q: Can I drive with a P179A code?
A: It is not recommended as it may lead to further transmission damage.
Q: Will resetting the code fix the problem?
A: Resetting the code may temporarily clear the warning light, but the underlying issue needs to be addressed to prevent recurrence.
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