C1352 – Increasing pressure solenoid (right front) (Toyota)

Toyota-specific code — factory diagnostic data

C1352 means your Toyota C-HR has a fault the brake control system associates with the right front “increasing pressure” solenoid circuit. Most drivers notice ABS, traction control, or stability control warnings first. Braking still works, but the vehicle may lose ABS/VSC/TRC assist during hard stops or slippery conditions. According to Toyota factory diagnostic data, this is a manufacturer-specific chassis code defined as “Increasing pressure solenoid (right front).” That definition points you toward the hydraulic control unit’s solenoid control for that wheel circuit. It does not prove the solenoid itself failed.

C1352 Quick Answer

C1352 on a Toyota C-HR points to a problem in the right front brake pressure-increase solenoid control circuit inside the ABS/VSC/TRC system. Verify power, ground, wiring, and actuator control before replacing the hydraulic unit.

What Does C1352 Mean?

Official definition: “Increasing pressure solenoid (right front).” In plain terms, the ABS/VSC/TRC system saw an electrical or functional problem while trying to command the solenoid that raises hydraulic pressure for the right front brake circuit. In practice, that can disable ABS, traction control, and stability control functions that rely on precise pressure modulation.

What the module checks and why it matters: The ABS/VSC/TRC module monitors the solenoid driver circuit response when it commands the pressure-increase solenoid on or off. Depending on Toyota platform design, it may watch current flow, circuit continuity, and driver feedback to detect open circuits, shorts, or an abnormal load. This matters because the DTC only identifies a suspected trouble area. You must confirm whether the fault sits in wiring/connectors, the actuator assembly, power/ground integrity, or the control module driver.

Theory of Operation

Under normal conditions, the Toyota C-HR ABS/VSC/TRC actuator uses pump and solenoid valves to control brake pressure. During ABS or stability events, the module rapidly increases, holds, or decreases pressure at each wheel. The “increasing pressure” solenoid opens or routes fluid so the system can build pressure when the module requests more braking at that corner.

C1352 sets when the module commands the right front pressure-increase solenoid and the circuit feedback does not match expectations. An open harness, high resistance at a connector, a short to power or ground, or an internal actuator fault can all trigger the same DTC. A weak power supply or poor ground can also mimic a solenoid problem because it changes driver current under load.

Symptoms

You typically see chassis control warnings and reduced ABS/VSC/TRC function when C1352 sets.

• Warning lights ABS, VSC, TRAC, and brake system indicators illuminated
• Drive feel traction control and stability control interventions reduced or unavailable
• ABS operation ABS may not activate during hard braking or may stop mid-event
• Brake behavior longer stopping distance on slick roads due to loss of modulation
• Pedal feedback unusual pulsation or no pulsation during an ABS stop
• Stored codes related ABS/VSC/TRC actuator or solenoid circuit DTCs may appear together
• Intermittent fault warnings may clear and return after bumps, rain, or connector movement

Common Causes

• Open circuit in the right-front increasing pressure solenoid control wiring: A break in the harness stops current flow, so the ABS/VSC/TRC module sees no electrical response when it commands the solenoid.
• Short to ground on the solenoid control circuit: A rubbed-through wire can pull the circuit low, which prevents proper coil control and triggers a solenoid circuit fault.
• Short to power on the solenoid control circuit: A contact with a B+ feed can hold the circuit high, so the module cannot modulate the solenoid as designed.
• High resistance from corrosion or water intrusion at the actuator/solenoid connector: Added resistance limits coil current and can make the module flag an increasing pressure solenoid malfunction under certain conditions.
• Poor ABS actuator power or ground integrity: Voltage drop on actuator feeds or grounds can change solenoid current and confuse the module’s internal driver monitoring.
• Internal fault in the ABS actuator assembly (solenoid coil or driver stage): An electrically damaged coil or failing driver transistor can cause an out-of-range current/voltage pattern during self-checks and active control.
• Connector pin fitment issues (spread pins, backed-out terminals): Intermittent contact can pass a quick continuity test but fail under vibration, heat, or commanded solenoid load.
• Harness damage near the actuator bracket or along the right-front routing path: Tight bends and bracket contact can chafe insulation and create intermittent opens or shorts during body movement.

Diagnosis Steps

Use a scan tool that can access Toyota ABS/VSC/TRC data, run active tests, and view freeze frame. You also need a quality DMM, back-probing leads, and wiring diagrams for the C-HR. Have basic hand tools for connector inspection. Use a battery maintainer during extended testing to keep system voltage stable.

1. Confirm C1352 in the ABS/VSC/TRC module and record all DTCs. Save freeze frame for C1352 and note battery voltage, ignition state, vehicle speed, and any brake/ABS command states shown. Freeze frame shows when the module set the fault. Use a scan tool snapshot later to catch an intermittent drop during a wiggle test or drive.
2. Check related fuses and power distribution before testing at the actuator or module connector. Inspect fuse contacts for heat discoloration and loose fit. Also perform a quick visual check of the actuator harness routing and any recent repair areas. This prevents chasing a “bad solenoid” when the problem is a feed issue.
3. Verify ABS actuator power and ground integrity with voltage-drop testing under load. Command an ABS pump/solenoid active test if the scan tool supports it, or use a condition that powers the unit per Toyota service information. Measure voltage drop on the main power feed and on the ground path while the unit operates. Keep ground drop under 0.1V with the circuit operating.
4. Inspect the ABS actuator electrical connector and the right-front related terminals closely. Look for moisture tracks, green corrosion, bent pins, spread terminals, and backed-out locks. Perform a light tug test on each wire at the connector body. Repair terminal fitment issues before any component replacement decisions.
5. Clear DTCs and cycle the ignition to see how the code returns. A hard circuit fault monitored by the comprehensive component logic often reappears quickly at key-on. If C1352 only returns after driving or braking events, treat it as intermittent and lean harder on wiggle testing and snapshots.
6. Use the scan tool active test for the increasing pressure solenoid, if available for the Toyota C-HR platform. Listen for a consistent click pattern and watch ABS/VSC/TRC data PIDs that reflect solenoid command or actuator status. If the module commands the solenoid but reports an abnormal response, you now have a direction. Do not conclude the solenoid failed until circuit checks support it.
7. Key OFF, disconnect the ABS actuator connector, and check the solenoid circuit for shorts to ground and shorts to power. Measure resistance from the suspect control circuit to chassis ground, then to battery positive through the harness side. A short often shows up here without guessing coil values. If readings change during harness movement, isolate the chafe point.
8. Check the harness for an open circuit between the actuator connector and the module driver location per the wiring diagram. Use end-to-end continuity as a screening test, then load the circuit to prove it can carry current. A circuit can show continuity and still fail under load due to a few strands hanging on. If you lack a factory load tool, use a fused test light method approved by service practices and avoid overloading module drivers.
9. If wiring checks pass, evaluate connector pin tension and contact quality with a pin drag test tool or terminal test probes. Focus on the solenoid control and return paths shown in Toyota wiring. Many “solenoid” codes come from micro-fretting or spread terminals, not a bad actuator. Correct the terminal condition and retest before replacing assemblies.
10. If the circuit and terminals test good, suspect an internal ABS actuator issue next. Confirm by repeating the active test while monitoring supply voltage drop and observing whether the fault sets consistently during the command. If the driver stage fails, the code often sets under command even with stable power and known-good wiring. Follow Toyota service information for actuator replacement and any required calibration or linear solenoid offset procedures.
11. After repairs, clear DTCs and run the same active tests and a controlled road test. Use a scan tool snapshot during braking events to verify the solenoid command and system status remain stable. Recheck for pending versus confirmed status after at least one full drive cycle. Confirm the ABS/VSC/TRC lights stay off and no related codes return.

Professional tip: Treat C1352 as a “suspected circuit/actuator area” code, not a confirmed bad solenoid. Toyota’s ABS/VSC/TRC driver monitoring reacts to current patterns, so low system voltage, high resistance grounds, and weak connector tension can mimic a failed coil. Prove power and grounds with voltage-drop under load first. Then prove the control circuit can carry current before you touch parts.

Possible Fixes

• Repair power or ground voltage-drop issues at the ABS actuator: Clean and secure the ground point, repair damaged feed wiring, and correct fuse block contact problems proven by testing.
• Repair wiring faults in the right-front increasing pressure solenoid circuit: Fix opens, shorts to ground, or shorts to power found during isolation and wiggle testing.
• Service connector and terminal problems: Remove corrosion, restore pin fitment, replace damaged terminals, and ensure weather seals seat correctly.
• Replace the ABS actuator assembly only after circuit verification: Replace the unit when testing shows an internal solenoid coil or driver-stage fault and wiring integrity checks pass.
• Perform required Toyota setup after repairs: Complete any actuator initialization, calibration, or bleed procedures required by the ABS/VSC/TRC system after component or hydraulic service.

Can I Still Drive With C1352?

You can usually drive a Toyota C-HR with C1352, but you must treat it as a brake-control warning. This DTC points to the right front increasing pressure solenoid circuit or its control path in the ABS/VSC/TRC hydraulic unit. When the module cannot control that solenoid correctly, it may reduce or disable ABS, traction control, and stability control. Normal base braking often remains, but wheel slip control and panic-stop stability can change. Avoid hard braking tests on public roads. Increase following distance and reduce speed in rain, snow, or gravel. If the brake pedal feel changes, the ABS pump runs constantly, or multiple brake warnings appear, stop driving and diagnose it.

How Serious Is This Code?

C1352 ranges from an inconvenience to a real safety concern, depending on what failed. If the issue involves a momentary connector contact, you may only lose ABS/VSC/TRC and see warning lights. That still matters in low-traction conditions. If the fault involves a power, ground, or internal hydraulic control problem, the system can behave unpredictably during an ABS event. Some Toyota strategies also disable related functions when they see solenoid control faults. Do not ignore it if you tow, drive in mountains, or commute in bad weather. Treat any added symptoms, such as a hard pedal or abnormal noises, as a higher priority. The safest approach is prompt circuit verification before parts decisions.

Common Misdiagnoses

Technicians often replace the ABS actuator assembly too early because the code mentions a solenoid. That mistake happens when they skip circuit checks at the actuator connector. A solenoid code can set from harness damage, water intrusion, terminal spread, or a poor ground that only fails under ABS pump load. Another common error involves chasing the right front wheel speed sensor, since the code says “right front.” This DTC targets the increasing pressure solenoid, not wheel speed input. Shops also misread freeze frame data and ignore an intermittent history pattern. Confirm the fault repeats with an active test, then prove the control circuit integrity with resistance and voltage-drop tests under load.

Most Likely Fix

The most common confirmed repair directions for C1352 on a Toyota C-HR involve restoring electrical integrity at the ABS/VSC/TRC actuator connector or repairing the harness between the module and the hydraulic unit. Corrosion, backed-out pins, and terminal tension problems can interrupt solenoid current. After wiring checks pass, the next most frequent direction involves an internal fault in the ABS actuator assembly that prevents proper solenoid actuation. Do not treat that as certain. First verify power and ground quality under load, then use a scan tool active test to command the increasing pressure solenoid and confirm the module sees the expected response. Road-test to confirm the code does not reset under ABS enable conditions, which vary by Toyota system logic.

Repair Costs

Repair cost depends on whether the fault is wiring, a solenoid, a valve body component, or internal transmission diagnosis. Confirm the root cause with scan data before committing to a repair.

Last updated: April 9, 2026