2015 Fiat 500L - P0700 Transmission MIL and Getting Stuck in Gear

Question

My 500L is throwing a P0700 code and won't shift out of first gear unless I cycle the key. Sometimes the dash shows 'Check Transmission' and the car feels like it is stuck in limp mode. It seems to happen more often when the car is hot after sitting in traffic.

Jake Morrison · Accepted Answer

The issue was the Input Speed Sensor (ISS) and a loose pin at the TCM harness connector. I replaced the Input Speed Sensor (Part #68120434AA) which cost about $45 and cleaned the connector pins with DeoxIT. After performing the 'Clutch Kiss Point' relearn procedure using a professional tablet, the car has been shifting perfectly for three weeks. Total repair cost was under $100 for parts and fluid.

Carlos Diaz · Answer

On the Euro Twin Clutch Transmission (DDCT), check the hydraulic actuator fluid level (Selespeed fluid). If the reservoir is low, the pump won't maintain pressure and it will trip the MIL.

hd_trucker_77 · Answer

Check the ground strap located under the battery tray. These Fiats are notorious for bad grounding which causes noise on the CAN bus, leading the TCM to lose communication and trigger a P0700.

wrenchqueen · Answer

P0700 is just a generic code telling the ECM that the TCM has a problem. You need a scan tool that can talk directly to the Transmission Control Module to see the specific sub-codes, otherwise you are just guessing.

2015 Fiat 500L - P0700 Transmission MIL and Getting Stuck in Gear

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