Faulty ignition coil H (open primary winding or failed internal driver); Damaged, chafed or broken wiring in the coil H control circuit; Corroded, loose or pushed-out pins in the coil connector or ECM connector; Missing or poor power supply or earth to the coil; Blown fuse or faulty relay feeding the ignition coils; Fault within the engine control module driver circuit.

P0358

Ignition Coil H Primary Control Circuit/Open.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
3: AreaIgnition system or misfire
58: FaultThe specific fault in that area

What it means

P0358 means the engine control module has detected an open circuit in the primary control circuit for ignition coil H, which is normally the eighth coil on an engine with individual coils per cylinder. The module monitors the coil driver and its feedback, and it set the code because the expected signal was missing or out of range. Coil letter to cylinder mapping depends on the engine, so confirm it for the vehicle.

Symptoms

Engine misfire, particularly under load or acceleration
Rough idle or hesitation
Illuminated check engine light, possibly flashing during a severe misfire
Reduced power or poor fuel economy
Difficulty starting or an occasional stall
Fuel smell from the exhaust due to unburnt fuel

Possible causes

Faulty ignition coil H (open primary winding or failed internal driver)likely
Damaged, chafed or broken wiring in the coil H control circuitlikely
Corroded, loose or pushed-out pins in the coil connector or ECM connectorlikely
Missing or poor power supply or earth to the coilpossible
Blown fuse or faulty relay feeding the ignition coilspossible
Fault within the engine control module driver circuitrare

How to diagnose

Read all stored codes and freeze frame data to see engine load, speed and temperature when the fault set, and note any misfire codes
Confirm which cylinder coil H serves using the manufacturer data for that engine
Visually inspect the coil connector, wiring and nearby harness for damage, heat, oil contamination or corrosion
Swap coil H with a coil from another cylinder, clear the codes and see whether the fault follows the coil
Check the coil supply voltage and earth with the ignition on, following the wiring diagram
Test the control wire for continuity back to the ECM and for shorts to earth or supply, with the connectors disconnected
Check the relevant fuses and relays for the ignition system
Inspect the spark plug in that cylinder, as a worn plug can stress the coil, and check the ECM connector pins last

How to fix

Replace ignition coil H if it fails testing or the fault follows the coil
Repair or replace damaged wiring in the control circuit
Clean or repair the connector terminals, or replace the connector if the pins are damaged
Restore the power supply or earth, and replace any faulty fuse or relay after finding why it failed
Replace worn spark plugs at the same time as a coil to prevent a repeat failure
Repair or replace the engine control module only after wiring and coil have been proven good

Can I keep driving?

Medium severity

The car can usually be driven short distances to a workshop, but avoid heavy loads and long journeys. A continuing misfire can overheat and damage the catalytic converter, so if the warning light flashes, reduce speed and stop driving as soon as it is safe.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.