Have you suddenly seen a mysterious P0700 code pop up on your Jeep’s dashboard? That little check engine light can be annoying, but don’t panic – this guide will walk you through everything you need to know about Jeep’s infamous P0700 trouble code.
We’ll cover what the P0700 code means, common causes, diagnostic steps, and potential fixes so you can get back to enjoying your Jeep. Whether you drive a Wrangler, Cherokee, Grand Cherokee or other Jeep model, read on to learn why P0700 happens and how to address it.
Table of Contents
What is the P0700 Code?
The P0700 code indicates there is an issue with your Jeep’s transmission control system. It’s one of the most common trouble codes for Jeeps across different models and years.
Specifically, P0700 means there is a malfunction detected in the transmission control module (TCM) by the powertrain control module (PCM). The TCM is the computer that controls automatic transmission operation. The PCM sets the P0700 code when it stops receiving proper signals from the TCM.
You may see P0700 described as:
- Transmission control system malfunction
- Transmission control module request signal malfunction
- Trans control system malfunction
It’s essentially the computer’s way of telling you something is wrong with the communication between transmission components. The automatic transmission is unable to operate normally when this vital communication is disrupted.
Seeing a P0700 code will cause your Jeep’s check engine light to illuminate. It can also trigger limp mode which forces your Jeep into a lower gear with reduced engine power. This protects the transmission from damage while the code is active.
What Causes the P0700 Code in Jeeps?
There are a few common issues that can trigger the dreaded P0700 code in your Jeep:
- Faulty transmission control module (TCM) – The TCM is essentially the brain of the transmission. If it malfunctions or fails, it can no longer properly communicate with other components. This will switch on the check engine light and P0700 code.
- Damaged wiring and connections – Faulty wiring leading to solenoids, sensors or the TCM itself can cause connection issues. Damaged or corroded wires and pins prevent proper communication signals.
- Failed sensors – Sensors like the input/output speed sensors provide vital data to the TCM. If they malfunction, it causes the transmission control system problems.
- Low transmission fluid level – Insufficient transmission fluid can upset operation and lead to overheating. This can sometimes confuse the PCM and trigger a P0700 code.
- Shift solenoid failure – Automatic transmissions use shift solenoids to engage gears. If they get stuck or stop functioning, it disrupts shifting and the TCM setting the P0700 code.
- Torque converter issues – Malfunctions with the torque converter can affect input/output speeds seen by sensors leading to a P0700.
Those are the most common culprits for Jeep’s P0700 trouble code. The specific root cause depends on your model, mileage and maintenance history. Proper diagnosis is needed to pinpoint the issue on your Jeep.
Common Jeep Models That Get the P0700 Code
The P0700 code can popup on just about any Jeep model with an automatic transmission. Some of the most common include:
- Jeep Wrangler – Especially the JK and JL generations equipped with the 545RFE transmission.
- Jeep Grand Cherokee – Models with the 545RFE like the WJ generation seem especially prone to P0700 codes.
- Jeep Liberty – The KJ Liberty with the 42RLE transmission frequently sees P0700 trouble codes.
- Jeep Commander – Issues with the 545RFE transmission lead to this code.
But really any Jeep with a fault in the transmission control system can produce the P0700 code. Even manual transmissions can generate it in rare cases.
The important thing is properly diagnosing and repairing the underlying problem – not just the model of Jeep itself. Let’s look at some common symptoms associated with P0700 next.
Symptoms of P0700 Code
The P0700 trouble code might be present without any noticeable symptoms beyond the check engine light. But in many cases, you’ll experience some of these issues when the code is active:
- Check Engine Light – This will definitely come on if a P0700 code is present. It’s required by the OBD-II diagnostic system.
- Transmission slipping – Slipping between gears can indicate low fluid, solenoids not engaging, or other mechanical issues detected by the P0700 code.
- Delayed gear engagement – Does it take longer than normal for your Jeep to switch gears? This delayed engagement can accompany a P0700.
- Lack of power – Reduced engine power and acceleration is common as the transmission operates in fail-safe/limp mode.
- Transmission won’t shift – In severe cases, the transmission may lose the ability to shift properly. Being stuck in one gear is a serious symptom.
- Problems switching to reverse/drive – Difficulty shifting out of park into drive or reverse can also indicate issues detected by the P0700 code.
- Check engine light flashing – A flashing check engine light indicates severe transmission damage. Don’t ignore this warning if you have a P0700!
- Burning smell – Bad transmission fluid or overheating components can produce a burning odor when the P0700 code is active.
Monitor for any of these potential symptoms if you see the P0700 trouble code pop up. It can help you identify transmission problems and stay safe until repairs are made.
Diagnosing the P0700 Code
Diagnosing P0700 code problems in your Jeep takes some investigation and often involves the following troubleshooting steps:
Scan for Codes
First, scan your Jeep for trouble codes using an OBD2 scanner tool. This will reveal the P0700 code and any other related issues. Knowing all logged fault codes helps accuracy in troubleshooting.
Check Transmission Fluid
One easy thing to check is the transmission fluid level and condition. Low fluid can sometimes trigger the P0700 code. Check the dipstick with the engine warm in park and top it off if needed. Look for any signs of leaking as well.
Inspect Wiring and Connections
Since wiring faults are a frequent P0700 cause, take time to inspect the harness leading to transmission solenoids, sensors and modules. Look for chafed, cut or burnt wires. Make sure connections are clean and secure.
Test Sensors and Solenoids
Verifyproper sensor readings and operation of solenoids using scanner data and physical tests. Faulty input or output speed sensors, for example, are common with P0700 codes.
Assess Transmission Performance
Take the Jeep for a test drive if safely possible. Feel for any slipping, hesitation or flaring issues that point to mechanical problems the P0700 has detected. Be ready to stop if driving becomes dangerous.
Transmission Shop Diagnosis
For complex or intermittent issues, getting a professional transmission shop diagnosis may be needed. They have the tools and experience to fully assess transmission control system problems.
Thorough troubleshooting is key before making repairs for P0700 codes. You need to pinpoint if the issue is with solenoids, speed sensors, wiring, fluid, or the TCM itself. Rushing into repairs without understanding the root cause often leads to wasting money and frustrating continued problems.
How to Fix P0700 Code?
Repairing P0700 trouble codes requires fixing the specific issue uncovered during diagnosis. Here are some of the most common P0700 repairs:
- Fluid and Filter Change – Low fluid levels or contaminated fluid can sometimes trigger the code. A complete flush and fluid replacement is recommended.
- Module Reset – After other repairs, resetting and relearning the PCM and TCM can clear stored P0700 codes.
- Sensor Replacement – Faulty speed sensors and switches will need to be replaced if causing the problem.
- Wiring Repairs – Chafed or damaged wires leading to solenoids, sensors and modules may need splicing or full replacement.
- Solenoid Replacement – Stuck or bad solenoids must be swapped out to restore proper shifting ability.
- TCM Replacement – If the module itself is defective, a new transmission control module will be required.
- Valve Body Service – Issues in the valve body like stuck valves can lead to P0700 codes and require overhaul or replacement.
For DIY repairs, the warranty and skill level required depends on the specific issue. Seek help from a professional transmission shop for involved transmission disassembly or programming needs.
Is the P0700 Code Serious?
The severity of P0700 trouble codes varies greatly based on the underlying problem:
- A basic sensor failure or loose wiring connection causing a P0700 is not immediately serious if repaired promptly.
- Low fluid levels or contaminated fluid triggering the code can lead to accelerated wear if ignored.
- Electrical issues like faulty solenoids or TCM failure are serious as they usually worsen over time.
- Mechanical problems detected by P0700 like valve body or torque converter damage can quickly lead to complete transmission failure if not addressed.
The P0700 code itself is not serious and just indicates a problem needs attention. But the resulting symptoms it causes require diagnosis and repair as soon as safely possible. Driving long distances or hauling heavy loads with an active P0700 is not recommended.
Preventing P0700 Codes
While not always preventable, you can reduce P0700 code occurrences by:
- Regular transmission fluid and filter changes based on your Jeep’s maintenance schedule.
- Quickly fixing leaks, low fluid levels, or dirty fluid if they occur.
- Addressing any transmission problems promptly before small issues lead to larger ones.
- Using quality OEM or premium aftermarket parts when repairs are needed.
- Keeping wiring protected from damage that could cause connection faults.
No maintenance program can fully prevent P0700 codes. But staying proactive with service and repairs based on your Jeep’s needs gives you the best odds of avoiding problems.
P0700 Code – The Bottom Line
Seeing the P0700 trouble code appear can be worrying but know it’s a common issue with repairable causes. With proper diagnosis and the right repairs, your Jeep’s transmission can get back to smooth, reliable shifting.
Always have the code investigated and corrected promptly by a transmission shop to prevent further damage. Driving with the check engine light and symptoms caused by P0700 can lead to costly transmission failure. But addressing it early using the steps outlined in this article will typically have you back on the road worry-free.
The P0700 code and finicky automatic transmissions may feel frustrating at times. But have patience, work with an experienced technician, and get your Jeep’s transmission control system back in top shape. Before you know it, the open road will be calling your name once again!