P0685 on Jeep: How to Diagnose & Fix
ECM/PCM Power Relay Control Circuit/Open
1 Jeep model · 1 documented issue · 1 critical · $100-$1,200 repair
P0685 on Jeep by model: symptoms, diagnosis and fix
The TIPM is the integrated fuse/relay power-distribution module controlling most electrical systems. On many 2007-2018 Chrysler/Jeep vehicles, including the JK Wrangler, the internal fuel-pump relay (and later the other relays) degrades. The first symptom is usually a fuel-pump-relay problem causing hard starts, no-start, or stalling; failures can also present as random gremlins — fuel pump running with the key off, wipers or door locks cycling on their own, or intermittent electrical loads. While Chrysler recalled the 2011-2013 Grand Cherokee/Durango with an external relay, the Wrangler was generally not recalled, leaving owners to repair the module themselves. Dealer TIPM replacement runs ~$1,000-$1,200; repair/rebuild services and external-relay bypass kits are cheaper alternatives.
Common Symptoms
- Hard start, no-start, or stalling (fuel pump not priming)
- Fuel pump running with the ignition off
- Random electrical behavior — wipers, door locks, or lights cycling on their own
- Intermittent dead-vehicle conditions
How to Fix
Confirm the fuel-pump relay as the failure point (fuel pump not priming, no-start). Options: rebuild/repair the existing TIPM (specialist services), install an external fuel-pump relay bypass kit, or replace the TIPM (dealer ~$1,000-$1,200; module ~$400 plus programming). An external relay bypass is the common low-cost fix for the fuel-pump-relay failure mode.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- MAKS TIPM-7 fuel-pump-relay bypassOEMMAKS TIPM-7-FUEL-PUMP-RELAY-BYPASS
Bypass a test-confirmed failed internal fuel-pump relay while retaining ASD safety behavior Fitment/availability: 2012-2018 Wrangler JK with TIPM-7; manufacturer lists all Wrangler variants through 2018.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (3)
P0685 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0685 mean on a Jeep?
P0685 stands for "ECM/PCM Power Relay Control Circuit/Open." An open or general fault in the control circuit for the ECM/PCM main power relay. The module cannot properly control the relay that supplies its own switched power. On Jeep it is documented across 1 model: Wrangler.
What are the most common causes of P0685?
The most common causes of P0685 are: Faulty ECM/PCM power relay, Open in the relay control circuit, Corroded/damaged connectors, Blown fuse, Internal PCM driver fault. The specific cause varies by vehicle.
How much does it cost to fix P0685 on a Jeep?
Published repair estimates on Jeep range from $100 to $1,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0685 on a different make?
View P0685 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.