Faulty or sticking fuel injector number 6 (internal coil or mechanical issue); Damaged or corroded electrical connector at injector 6; Chafed, cracked, or broken wire in the injector 6 circuit (power or ground side); Loose or backed-out terminal in the injector harness connector; PCM driver circuit fault for injector 6 (rare but possible); Moisture intrusion into the injector connector or wiring harness

DTC codes / Chrysler codes / P1237

P1237 · ChryslerInjector Circuit Cylinder 6 Intermittent

Q: What does code P1237 mean?

Injector Circuit Cylinder 6 Intermittent. P1237 on a Chrysler vehicle indicates that the powertrain control module (PCM) has detected an intermittent fault in the electrical circuit for fuel injector number 6. The PCM monitors the injector driver circuit and sets this code when the current flow is inconsistent, meaning the circuit momentarily opens or shorts rather than failing completely.

P1237 on a Chrysler vehicle indicates that the powertrain control module (PCM) has detected an intermittent fault in the electrical circuit for fuel injector number 6. The PCM monitors the injector driver circuit and sets this code when the current flow is inconsistent, meaning the circuit momentarily opens or shorts rather than failing completely.

SystemPowertrain

Code typeChrysler specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illuminated check engine light, often with no other noticeable symptoms
Intermittent engine misfire or rough running, especially under load or at certain RPMs
Slight loss of power or hesitation during acceleration
Occasional rough idle that may come and go
Poor fuel economy if the misfire occurs frequently

Common causes, most likely first

Faulty or sticking fuel injector number 6 (internal coil or mechanical issue)
Damaged or corroded electrical connector at injector 6
Chafed, cracked, or broken wire in the injector 6 circuit (power or ground side)
Loose or backed-out terminal in the injector harness connector
PCM driver circuit fault for injector 6 (rare but possible)
Moisture intrusion into the injector connector or wiring harness

How to diagnose and fix it

Inspect the injector 6 electrical connector for corrosion, looseness, or damaged pins; clean or repair as needed
Perform a wiggle test on the injector 6 harness while the engine is running to check for intermittent faults
Measure the resistance of injector 6 with a multimeter and compare to specifications; replace if out of range
Check for continuity and short-to-ground on the injector 6 control circuit from the PCM to the injector
Swap injector 6 with a known-good injector from another cylinder to see if the misfire moves
If wiring and injector are good, test the PCM driver circuit with a noid light or oscilloscope
Replace the PCM only after all other causes have been ruled out and reprogram if necessary

Intermittent injector faults often hide in the harness

A common oversight is replacing the injector without checking the harness connector for intermittent contact; a loose pin can mimic a failing injector.
The code can set from a momentary glitch that does not store a misfire code, so the engine may run perfectly during a test drive.
Heat and vibration can cause a wire to intermittently short only when the engine is at operating temperature, so cold testing may miss the fault.
A faulty PCM is rarely the cause, but a driver circuit that fails only under load can be misdiagnosed as a bad injector.
Chrysler injector circuits often share a common power feed, so a problem on that feed can affect multiple injectors, but P1237 specifically flags cylinder 6.

Can I keep driving with P1237?

You can usually drive the vehicle with this code, but avoid heavy acceleration or towing until it is repaired, as an intermittent misfire can worsen and damage the catalytic converter over time.

Tools that help

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Guidance is general and written for Chrysler vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.