U302A

Code

Generic U — Network/User

Control Module A Disable Feedback Circuit High

Brand: Generic

Type: U — Network/User

Views: UK: 26 EN: 36 RU: 26

AI status

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Page language: EN

Causes

Open circuit or high-resistance connection in the disable/feedback wiring
Short to battery voltage on the disable/feedback line
Corroded or loose connector pins at the affected module or splice
Failed or internally shorted control module reporting the circuit high
Missing or incorrect pull‑down/pull‑up resistor on the feedback line (hardware or software configuration issue)
Aftermarket accessories or repairs that altered wiring, splices, or grounds

Symptoms

Related module functions disabled or intermittent
Network warnings or multiple communication-related trouble codes present
Indicator/warning lights related to the affected system(s)
Features controlled by Control Module A do not operate or respond
Fault remains after key cycles or is present intermittently

What to check

Read all stored and pending DTCs, note freeze frame and related U- or B-/P-codes
Inspect the connector and wiring for Control Module A for corrosion, damage, or water intrusion
Verify battery voltage and good chassis/engine grounds
Backprobe the disable/feedback circuit and measure voltage with key ON and engine OFF
Check for aftermarket devices or recent repairs in the circuit path
Perform wiggle test on harness while monitoring signal and DTC status

Signal parameters

Expected logic levels vary by vehicle: many disable/feedback lines are either pulled to ground (0 V) for active or pulled to battery (~12 V) for inactive; some systems use 0–5 V logic. Consult vehicle-specific spec.
Fault condition reported as 'High' — measured voltage typically near battery voltage (approx. 11–14 V) or above the expected maximum logic threshold (e.g., >4.5 V on a 5 V system).
Normal/Inactive low value: ~0–0.5 V (if low is active) or ~0–5 V depending on design — compare to OEM spec.
Measure continuity/resistance to ground or battery as required; expected continuity values dependent on module design and presence of pull resistors.

Diagnostic algorithm

Retrieve all codes and freeze frame; record which module is referenced as 'Control Module A' by vehicle documentation or scan tool.
Duplicate the fault condition by cycling key and attempting the affected function(s) while monitoring live data and the disable/feedback signal.
Visually inspect connectors, wiring harness, and nearby components for damage, corrosion, or water ingress; repair obvious damage.
With the connector attached, backprobe the disable/feedback circuit. Measure voltage with key ON (engine OFF) and with operation that should change the line; compare to spec.
If voltage is high, isolate sections of wiring: disconnect downstream modules or splices one at a time (observe safety and manufacturer procedures) to determine if the short/source follows the harness or is at the module.
Check for continuity/short to battery on the feedback wire: with battery disconnected, measure resistance from feedback wire to battery positive and to ground.
If wiring and connectors test good, check module ground integrity and supply voltages; if those are good and the line still reports high with the module disconnected, suspect an external short or incorrect harness modification.
If the wiring harness and power/grounds are OK and the circuit behaves correctly when the module is disconnected, suspect internal module failure — verify with OEM diagnostics before replacement.
Repair wiring, connector, or module as indicated, reprogram/initialize replacement module if required, clear codes and road-test to confirm repairs.
If intermittent, use monitoring tool to log the circuit while driving or during conditions that reproduce the fault.

Likely causes

Open connector or corroded pin at the module harness (common and likely)
Short to battery on the feedback/disable wire (wiring chafed against chassis or power source)
Failed module driving the feedback line high or reporting incorrect state
Missing/incorrect resistor or module configuration after replacement

Fault status

⚠️ Status

Control Module A Disable Feedback Circuit High — disable/feedback line voltage above expected threshold. Possible open/high resistance or short to battery on the feedback circuit or module fault. Verify wiring, connector, grounds, and module configuration.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours