What does it mean?
P1293 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Injector Circuit Low to High Current Transition Time Bank 1 .
Symptoms
- MIL (check engine lamp) on
- Rough idle and misfire on the affected bank
- Hard starting, worse when the engine is cold
- Hesitation and reduced power under load, sometimes with smoke on diesel applications
- Uneven running that gets better once the engine is fully warm
Likely causes
- High resistance in the Bank 1 injector feed or return wiring from corroded terminals or a poor splice
- Injector solenoid with drifted coil resistance or inductance
- Loose or backed-out terminals in an injector connector
- Low supply voltage to the injector driver module, from a weak battery, failing alternator or corroded ground
- Damaged output stage in the injector driver module
- Oil, fuel or coolant contamination inside the injector connectors
How to fix it
- Read the freeze frame and check for companion injector codes that narrow the fault to one cylinder
- Inspect and clean the Bank 1 injector connectors, looking for spread terminals and green corrosion
- Measure the resistance of each Bank 1 injector when cold and compare the values across the bank
- Perform a voltage drop test on the injector feed and ground while the engine cranks
- Verify battery and charging voltage under electrical load
- Run an injector current ramp or buzz test if the equipment is available and compare waveforms between cylinders
- Replace the out-of-specification injector or repair the harness, and consider the driver module only last