P1603 on Toyota
Engine stall history (Toyota)
Severity: Inspect soon
On Toyota, P1603 is a record that the engine stalled on its own. The car may restart and run normally, but whatever caused the stall can repeat in traffic, so get it diagnosed soon.
It gets more serious if:
- Stop: The engine stalls or loses power while driving, or will not restart. Owners report P1603 with stalls in moving traffic and engine failures. Get off the road safely and have the car towed or checked before driving again.
This page covers only what differs on Toyota. For what P1603 means, the ranked causes and the test order, see the P1603 guide.
What's different on Toyota
ToyotaYour car
2014–2018 · Highlander
Supported by vehicle dataCheck the engine computer connector for water and corrosion if an aftermarket windshield with a de-icer is fitted (T-SB-0072-19).
2018 · RAV4
Possible — needs testingAn owner reports repeated stalls in traffic with P1603, P1604 and P1605 recorded by Toyota and no root cause found. Owner report only.
T-SB-0072-19Status unverified
Toyota T-SB-0072-19: drivability and P1603-P1605 from ECM connector corrosion
2014–2018highlander · issued · NHTSA 10162756
Water and corrosion in the A43 engine computer connector, from poorly sealed aftermarket windshield de-icer harnesses, can cause drivability problems, low fuel pressure and codes including P1603, P1604 and P1605.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Sources and review
- Toyota T-SB-0072-19: Highlander ECM connector corrosion, P1603/P1604/P1605
- NHTSA complaint ODI 11205338: 2018 Toyota RAV4, dealer readout P1603 engine stall, P1605 rough idling
- TAT Scandata: P1603 (Toyota) Engine Stall History
- NHTSA complaint ODI 11733489: 2020 Toyota Corolla, P1603 Engine Stall History at a red light
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error