What is the code P0700 on a 2007 Chevy Cobalt?
P0700 is a general Transmission Control System Malfunction code. On a 2007 Chevy Cobalt, it signals a problem in the transmission control system or a communication fault between the engine control module (ECM/PCM) and the transmission control module (TCM); it does not pinpoint the exact issue by itself and is typically accompanied by other codes that identify the specific component or sensor involved.
What the code means for the 2007 Cobalt
In GM vehicles, P0700 serves as a catch-all for transmission control problems. It indicates the transmission control system has detected a fault and stored a diagnostic trouble code. To identify the root cause, you must pull additional codes from the PCM/TCM, especially any P0700-related codes in the P0700-P0799 range. These supplementary codes point to specific issues such as solenoids, sensors, or valve-body problems. If the vehicle shifts normally, P0700 alone may be incidental, but it should be investigated when accompanied by symptoms or other codes.
Common symptoms you may notice
Symptoms vary with the underlying cause, but several signs often accompany P0700 in a Cobalt.
If you notice any of these symptoms, have the vehicle diagnosed promptly to prevent further transmission damage.
Common causes of P0700 on a 2007 Chevy Cobalt
The following items are frequent culprits behind P0700 in this model, emphasizing transmission electronics, sensors, and related wiring.
Because P0700 is a general code, diagnosing the exact cause requires reviewing additional codes and performing targeted electrical and mechanical checks.
How to diagnose and fix P0700 on a 2007 Cobalt
Before starting, ensure you have a reliable OBD-II scanner capable of reading GM-specific codes and live data. The steps below outline a structured approach.
- Retrieve all stored DTCs beyond P0700 and review freeze-frame data to understand operating conditions when the fault occurred.
- Inspect transmission fluid level and condition; top up or replace if required and note any contamination.
- Inspect the wiring harnesses and connectors to the TCM, transmission range sensor, and speed sensors for damage, corrosion, or loose connections.
- Identify any P07xx or related codes that point to solenoids, valve body, or sensor faults; perform follow-up tests or component replacements as indicated by the codes.
- Check for GM service bulletins or software updates related to the transmission control system for the 2007 Cobalt; apply updates or reprogram as advised.
- If electrical checks pass, evaluate the TCM itself for faults; consider replacement or reprogramming if diagnostics indicate a defective unit.
- Conduct a road test after repairs and re-scan to confirm that the issue is resolved and no new codes appear.
In many cases, addressing P0700 involves fixing a faulty sensor, replacing a faulty solenoid, or updating software; some situations may require a TCM replacement or more involved transmission service.
Is it safe to drive with P0700?
If the car shifts normally and shows only P0700 without other codes, you may be able to drive cautiously to a repair shop. If you experience slipping, loss of power, or limp mode, reduce speed and have the vehicle towed to avoid possible transmission damage.
What to expect in repairs
Repair outcomes vary based on the underlying cause. Common scenarios include software updates, wiring repairs, solenoid replacement, valve-body service, or TCM replacement. In some cases, the root issue may be mechanical wear requiring more extensive transmission servicing.
Summary
P0700 is a catch-all GM code meaning Transmission Control System Malfunction. For a 2007 Chevy Cobalt, it signals an issue in the transmission control system or its communication with the PCM, and it should prompt a systematic diagnostic approach to identify and fix the underlying cause. By pulling all related codes, inspecting electronics and fluid, and following service information or bulletins, you can determine whether the fix is software, electrical, or mechanical and take appropriate action. Prompt diagnosis helps prevent further damage and costly repairs.
What is the code P0700 on a Chevy Cobalt?
The P0700 code indicates a problem with the transmission. It should not be ignored, because there can be serious drivability problems now and in the future. The technician should check for all codes present to accurately diagnose the problem.
How do you fix a P0700 transmission control system malfunction?
To fix a P0700 code, first check the transmission fluid level and condition, and address any low levels or dirty fluid. Next, use a scan tool to check for any additional transmission-specific codes, which can point to a faulty sensor, shift solenoid, or valve body. If the problem isn't obvious, inspect the transmission's wiring and electrical connectors for damage, corrosion, or poor connections, as well as the Transmission Control Module (TCM) itself.
Initial checks and simple fixes
- Check transmission fluid: Check the transmission fluid level and look for it to be dark or contain metal shavings. If it's low, add more fluid. If it's dirty, a fluid and filter change may be necessary.
- Clear the code: Disconnect the car battery overnight to reset the system, or use a scan tool to clear the code. If the code returns, a more in-depth diagnosis is needed.
- Inspect wiring: Visually inspect the wiring harnesses and electrical connectors for the transmission for any signs of damage, loose connections, or corrosion. Clean terminals and repair any damaged wires.
Further diagnosis and repairs
- Use a scan tool: A more advanced scan tool is crucial for this step, as it can read codes directly from the TCM, which the P0700 code is a request for. Look for additional codes (like P0721 for a speed sensor or P0746 for a shift solenoid) to pinpoint the exact problem.
- Replace faulty sensors: If a sensor like the output speed sensor is faulty, it will need to be replaced.
- Address internal components: If the problem is not with the fluid or wiring, it may be an internal issue. This could involve replacing a bad shift solenoid, valve body, or torque converter clutch.
- Check the TCM: The Transmission Control Module itself could be faulty and require replacement.
This video explains how to check the transmission fluid and look for signs of damage: 42sHVAC Mechanic YouTube · Mar 13, 2024
When to see a professional
- If you're uncomfortable: Transmission work can be complex. If you are not comfortable with these steps, it's best to take the vehicle to a qualified mechanic.
- If initial fixes don't work: If checking the fluid and wiring doesn't solve the problem, a professional can perform the necessary in-depth diagnostics to avoid making expensive mistakes.
This video discusses the importance of professional diagnosis and repair for transmission issues: 58sWeeklyToolsYouTube · Mar 24, 2024
Can dirty transmission fluid cause a P0700 code?
The P0700 code can be caused by low transmission fluid levels, dirty transmission fluid, a malfunctioning engine coolant sensor, slipping converter clutch, a bad valve body, or failing shift solenoids.
How much does it cost to fix a P0700 code?
The cost to fix a P0700 code varies significantly, from a few hundred dollars for simple issues like a transmission fluid change to several thousand dollars for major problems like a transmission rebuild. A simple diagnosis may cost around $150−$170$ 150 minus $ 170$150−$170, with labor costs varying based on the cause.
This video explains the cost variations for fixing a P0700 code based on the cause: 51sLearnToDIY360YouTube · Dec 14, 2024
Cost breakdown by potential repair
- Diagnostic fee: Initial diagnosis can range from approximately $155$ 155$155 to $170$ 170$170, depending on the shop, and often includes a credit towards the follow-up repair.
- Simple repairs:
- $120$ 120$120 to $500$ 500$500: Transmission fluid change:.
- $100$ 100$100 to $500$ 500$500: Wiring/connector repair:.
- More complex repairs:
- Sensor or shift solenoid replacement: Can range from a couple hundred dollars to over $1,000$ 1 comma 000$1,000, depending on the specific part.
- $2,500$ 2 comma 500$2,500 to $9,000$ 9 comma 000$9,000: Transmission rebuild or replacement: or more.
What the P0700 code means
- The P0700 code is a general "check engine" light for a transmission issue. It signals that a problem has been detected in the vehicle's transmission control system.
- It's a generic code that doesn't point to a specific problem, but rather indicates that another, more specific trouble code is being stored in the transmission control module (TCM).
- A proper diagnosis is crucial to determine the specific cause and the correct repair.
