B1358

Code

Other B — Body

Ignition Run Circuit Short To Ground

Brand: Other

Type: B — Body

Views: UK: 29 EN: 39 RU: 26

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Page language: EN

Causes

Damaged or chafed wiring harness on the ignition run circuit
Corroded, loose, or damaged connector at module, relay or ignition switch
Accessory/ignition relay stuck closed or shorted to ground
Aftermarket device or accessory improperly wired to ignition run circuit
Internal fault in control module or relay (rare)
Blown fuse or improper fuse installation that allowed alternate grounding path

Symptoms

Check Engine/Warning lamp illumination or body control module fault indicator
Certain ignition-switched accessories or modules inoperative or intermittent
Vehicle may not stay in RUN state; accessories may fail to operate
Blown or repeatedly failing fuses on ignition-switched circuits
Possible parasitic battery drain when key is OFF (if short is present)

What to check

Visual inspection of wiring and connectors along ignition run circuit (look for chafing, heat damage, corrosion)
Inspect ignition/auxiliary relays and socket for signs of burning or corrosion
Check fuses related to ignition run and associated modules for correct rating and condition
Disconnect aftermarket accessories that tie into ignition circuit and re-test
Use a wiring diagram to identify the ignition run feed and follow harness to modules and switches

Signal parameters

Ignition Run circuit voltage (Key ON, engine OFF): ~11–14 V expected
Ignition Run circuit voltage (Key OFF): ~0 V expected
Resistance from ignition run circuit to chassis ground (power off): very high/open (typically kilo-ohms to mega-ohms); near 0 ohms indicates short to ground
Current draw on ignition run feed (Key ON): minimal for control signals; large unexpected current indicates short/low resistance path
Module input pin should see key-switched voltage transitions when turning key to ON/RUN

Diagnostic algorithm

Safety first: park vehicle, set parking brake, disconnect battery if you will be performing resistance or connector repairs. Observe manufacturer procedures for airbag/body modules before disconnecting related connectors.
Retrieve freeze frame and module live data where available; confirm B1358 is active or in history and note conditions when set (key position, battery voltage).
Visual inspection: trace the ignition run wiring from the ignition switch/relay to the affected module(s). Look for melted insulation, pinched areas, corrosion, rodent damage, or water entry. Repair visible damage and clear codes, then retest.
With key OFF and battery disconnected, measure resistance between ignition run circuit conductor and chassis ground. If near 0 ohms, a short to ground exists — isolate by disconnecting connectors progressively along the circuit until the short is removed to find the section causing it.
With battery connected and key ON (engine off), measure voltage at the ignition run circuit at the module connector and at relay/ignition switch. Voltage should be battery voltage. If low, back-probe toward source to locate where voltage drops.
Test relays: remove and bench-test the ignition/auxiliary relay or swap with identical relay to check for internal short. Inspect relay socket for shorts.
Disconnect suspect modules or aftermarket devices one at a time and observe if code clears or circuit voltage returns to normal to identify a faulty module or accessory.
Perform wiggle/strain tests on harness connectors while monitoring circuit voltage or resistance to reproduce intermittent shorts. Repair or replace damaged harness sections using proper crimping/soldering and corrosion protection.
If wiring and external components check good and short persists, consider module internal fault. Verify with manufacturer service information and perform module bench testing or replacement per factory procedures.
After repair, clear faults, perform function tests, and road test (or cycle key states) to ensure code does not return. Reinspect repairs if intermittent issues recur.

Likely causes

Wiring pinch or abrasion causing insulation breach and contact with chassis ground
Connector terminal pushed out, corroded, or shorting to adjacent ground terminals
Failed ignition/auxiliary relay with coil or internal short to ground
Improperly installed aftermarket electronics tied into ignition circuit without proper isolation
Shorted branch circuit due to rodent damage or water intrusion

Fault status

⚠️ Status

Control module detected ignition run circuit shorted to chassis ground; circuit voltage below expected threshold or continuity to ground present. Fault stored when the module senses an abnormal low-voltage condition on the ignition run feed.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours