P1590 — cruise control distance increase signal

Can I keep driving with P1590?

Usually yes. P1590 mainly affects A/C compressor control and cooling, so drive only if the engine cooling system remains normal while arranging the repair.

Does P1590 prove that the A/C refrigerant level is low?

No. P1590 identifies the refrigerant-temperature sensor circuit; a refrigerant leak may coexist, but low refrigerant is not established by this code alone.

Should I replace the A/C compressor first?

No. Test the refrigerant-temperature sensor, connector, reference voltage, ground, and wiring before considering the compressor or A/C control module.

Will clearing P1590 with an ELM327 fix the problem?

Clearing removes the stored code only. If the sensor circuit remains faulty, P1590 will return after the controller detects the same invalid signal.

When your check engine light comes on and a scan tool shows P1590, you're looking at a stored fault involving sensor and actuator circuit performance. This code specifically points to an electrical problem somewhere in the related control circuit — the powertrain control module has detected a signal that falls outside the expected range or has gone completely silent.

Modern engines rely on a constant conversation between sensors that measure conditions and actuators that respond to commands. The PCM constantly compares what it receives from these circuits against factory-calibrated thresholds. When readings stray too far from normal — or disappear entirely — across multiple ignition cycles, P1590 gets logged and the freeze frame snapshot captures exactly what the engine was doing at that moment: RPM, load percentage, coolant temperature, and vehicle speed. That snapshot is invaluable when you're tracking down an intermittent problem.

P1590 is a generic powertrain code, meaning the same underlying logic applies across many manufacturers, though the exact component affected varies by vehicle. The code alone tells you something is wrong in a sensor or actuator circuit, but it doesn't name the part. That's where diagnosis begins.

Symptoms of P1590

The way P1590 shows up in the driver's seat depends on which circuit is actually at fault. Typical complaints include:

• The system tied to the faulty circuit stops working or works only intermittently
• The vehicle may enter limp mode, limiting power or certain functions until the issue is resolved
• Fuel economy can climb noticeably if the affected sensor or actuator disrupts normal engine operation
• The Check Engine Light stays illuminated until the fault clears
• In some cases, no obvious drivability symptoms occur at all — the problem only appears in stored data

Common Causes

The root cause behind P1590 almost always traces back to one of a handful of electrical culprits. The most frequent offenders, ranked roughly by how often they appear in the real world:

• Loose, corroded, or damaged connector contacts creating high resistance or intermittent connections
• Wiring that has chafed through, melted from heat, or been chewed by rodents, causing opens or shorts
• A failed sensor or actuator that no longer produces or responds to the correct signal
• Blown fuses that interrupt power to the affected circuit
• Poor ground connections starving the circuit of proper electrical reference
• In rare cases, an internal fault within the control module itself

How to Diagnose P1590

A systematic approach keeps you from replacing parts unnecessarily. Follow these steps:

1. Connect your OBD2 scanner and confirm P1590 is present. Record the freeze frame data — note the RPM, load, temperature, and speed values. Reproducing those exact conditions during your test drive makes the fault reappear faster.
2. Pull all stored codes, not just P1590. Related codes often point directly at the failing component. Check for any manufacturer TSBs (technical service bulletins) that apply to your make, model, and year — many issues have published fixes or software updates.
3. Visually inspect the wiring and connectors associated with the affected circuit. Look for broken insulation, corrosion buildup, bent pins, or connector housings that have come apart.
4. With the connector unplugged, check reference voltage, ground integrity, and signal wire continuity using a multimeter. Compare your readings to the values specified in your vehicle's repair manual.
5. Perform a wiggle test on the harness while monitoring live data. Any signal dropouts or wild fluctuations point to broken strands inside the wire.
6. Clear the code, then drive the vehicle through a complete drive cycle — including the conditions recorded in your freeze frame. If P1590 comes back, you've confirmed the fault is still present.

Repair Options and What They Cost

P1590 typically gets resolved by addressing whichever link in the circuit chain has failed. Here's what the repair usually involves and what you can expect to pay (parts and labor, USD, independent shop rates):

• Wiring harness or connector repair — When damage is localized, splicing in new wire or replacing terminals runs about $80–$250 depending on accessibility.
• Sensor or actuator replacement — If the component itself is dead, swapping it out typically costs $150–$500 depending on the part and labor time.
• Control module repair — In the rare event the PCM or TCM is at fault, expect to pay $300–$1,000 for professional repair or replacement.

Total Cost to Fix P1590

Your actual out-of-pocket cost hinges entirely on what caused the code. A straightforward wiring fix sits at the low end; a failed control module lands at the high end. Budget anywhere from $80 to $1,000. The smart move is getting a proper diagnosis before buying expensive parts — many shops will apply diagnostic fees toward the repair if you authorize the work. Tackling the easy checks yourself first (connectors, fuses, visible wiring) can narrow things down and keep your bill minimal.

Can You Drive with P1590?

In most cases, yes — the vehicle stays drivable. You might notice reduced performance, a disabled辅助 function, or slightly worse fuel economy, but the engine will run. However, if P1590 brings with it stalling, failure to start, or warnings related to braking or steering assist, treat it as urgent and stop driving it. Otherwise, schedule the repair at your earliest convenience.

Related OBD2 Codes

• P1500: Secondary Switch Solenoid Circuit Malfunction
• P1501: APLSOL Solenoid Circuit Malfunction
• P1502: RCNT Solenoid Circuit Malfunction
• P1503: SPCUT Solenoid Circuit Malfunction
• P1504: TCSPL Solenoid Circuit Malfunction
• P1505: Vehicle Speed Sensor Intermittent