Jeep DTC P1390 – Timing Belt Skipped One Tooth or More
DTC P1390 meaning on Jeep
DTC P1390 on a Jeep indicates that the Engine Control Module (ECM) has detected that the timing belt has skipped one tooth or more in relation to the camshaft and crankshaft positions.
Jeep DTC P1390 symptoms
- Engine misfires
- Loss of power
- Engine running rough
- Check Engine Light illuminated
Jeep DTC P1390 causes
- Worn timing belt
- Incorrect timing belt installation
- Timing belt tensioner failure
- Timing belt pulley misalignment
Jeep DTC P1390 seriousness
The seriousness of DTC P1390 lies in the fact that a skipped timing belt can cause significant engine damage if not addressed promptly. It can lead to valve-to-piston contact, resulting in bent valves or even more severe internal engine damage.
How to diagnose DTC P1390 on Jeep
To diagnose DTC P1390 on a Jeep, a mechanic would typically perform the following steps:
- Use a scan tool to retrieve the fault code and freeze frame data
- Inspect the timing belt for wear, damage, or misalignment
- Check the timing belt tension and tensioner for proper operation
- Verify the alignment of the timing belt pulleys
How to fix DTC P1390 on Jeep
To fix DTC P1390 on a Jeep, the following steps are generally taken:
- Replace the timing belt if worn or damaged
- Ensure correct installation of the timing belt with proper tension
- Replace the timing belt tensioner if faulty
- Correct any misalignment of the timing belt pulleys
How to erase DTC P1390 on Jeep
After fixing the underlying issue causing DTC P1390 on a Jeep, the fault code can be erased using a scan tool. This will clear the code from the ECM’s memory and turn off the Check Engine Light.
Recommended tools for Jeep diagnostics
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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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