P1790 Chevrolet Code - Transmission Control Module Checksum
Quick Answer
The P1790 code for Chevrolet vehicles specifically refers to a Transmission Control Module (TCM) Checksum error. Common causes include Electrical interference, Failing TCM, Software glitches. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1790 Chevrolet indicates Transmission Control Module Checksum.
- Common causes
- Common causes include Electrical interference, Failing TCM, Software glitches.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P1790 Chevrolet Description
The P1790 code for Chevrolet vehicles specifically refers to a Transmission Control Module (TCM) Checksum error. The TCM is a vital component of the vehicle's transmission system, responsible for controlling various functions such as gear shifting, torque converter locking, and overall transmission performance. The checksum is a value calculated from the data within the TCM to ensure that it has not been corrupted or tampered with. When the TCM detects a checksum error, it means that the data within the module has been compromised or is not matching the expected values.
Common Causes of P1790 Chevrolet
- Electrical interference
- Failing TCM
- Software glitches
- Transmission wiring harness issues
Symptoms of P1790 Chevrolet
- Erratic shifting patterns
- Transmission slipping
- Harsh shifting
- Transmission stuck in a single gear
- Poor fuel economy
How to Fix P1790 Chevrolet
- Diagnose the specific cause of the checksum error by using a diagnostic scanner to read the TCM data and identify any potential issues.
- Inspect the transmission wiring harness for any damage or loose connections and repair or replace as needed.
- Update the TCM software to the latest version provided by Chevrolet to address any potential software glitches.
- If the TCM is determined to be faulty, replace it with a new or remanufactured unit and reprogram it to match the vehicle's specifications.
- Clear the error code from the TCM memory and perform a test drive to ensure that the transmission is functioning correctly.
Cost to Fix P1790 Chevrolet
The typical repair costs for addressing a P1790 code can range from $200 to $800, depending on the specific cause of the issue and the required repairs. This estimate includes the cost of parts such as a new TCM, wiring harness, or software update, as well as labor costs for diagnosis and repair. It is important to note that the actual costs may vary based on the location, vehicle make and model, and the rates charged by the auto repair shop. It is advisable to obtain multiple quotes and compare prices before proceeding with the repair.
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Frequently Asked Questions about P1790 Chevrolet Code
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Discuss the causes and fixes for P1790 Chevrolet OBDII Code
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so you want info? Okay , 2016 chevy spark replaced the transmission with a known good used one. P1790 is the nsame code that I had before the R/R. My Snapon scaner dose not have the program to re learn the TCM. So, took it to the dealer, dealer said they did the relearn but the car will not go in reverse . Had it towed back to the shop and drove it off the truck and into the shop, in reverse. Still have a P1790 code. Sooo, the question is, if the dealer up dated the soft ware as per the TSB why do I still have that code???
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I haven't had that problem before, but according to a national database of repairs for your model year, if the code persists after reprogramming the TCM, then the next step is replace the TCM. Unfortunately, other than that I no more information.
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