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What This Part Covers

A cracked mirror glass or a defroster that never clears is a same-week repair on these Lexus platforms. The Koeep Left/Right Mirror Glass Heated w/ Backing for Lexus is a heated replacement with a pre-bonded backing plate, cross-referenced to OEM part numbers 87961-76020 (Right/Passenger) and 87931-76020 (Left/Driver).

Fitment covers seven variants: LS460 (2013–2017), CT200h (2011–2017), ES300h and ES350 (2013–2018), GS450h and GS350 (2013–2015), and LS600h (2013–2017). One SKU covers both sides across the 2011–2018 model year spread.

Market context for 2026: Future Market Insights projects global automotive glass at USD $23.5 billion, a 5.7% CAGR through 2036, and Toyota keeps refining TNGA-L thermal management into the 2026 model cycle. A heater that tracks OEM behavior keeps the body control module quiet.

Spec Comparison: Koeep vs Lexus OEM vs Economy Aftermarket

Economy glass is where the differences show: float glass instead of tempered, low heater draw, and resistance outside the range the BCM expects. Data comes from manufacturer specifications, SAE J673:2024, the FMI Automotive Glass Market Report 2026, and Toyota/Lexus service documentation.

How the Assembly Is Built

A screen-printed silver-ceramic resistive element is laminated between the tempered substrate and the injection-molded ABS backing plate. FMI puts this architecture at 66.5% of the 2026 automotive glass market. Heat spreads evenly across the full reflective surface, without the cold spots that degrade defrosting in sub-zero weather.

Tempered glass substrate

The 2.8mm ±0.1mm substrate meets ISO 3536 optical clarity standards with under 90 Haze per ASTM D1003. Edge compression exceeds 10,000 psi, and fragmentation testing yields 250 or fewer pieces in a 50mm × 50mm zone at breakage, clearing the FMVSS 111 rear-visibility minimum.

Heating element

Silver-palladium (Ag-Pd) traces run at 12V DC with an 18–22W nominal draw per mirror. Resistance sits between 6.5 and 8.0 Ω at 25°C ambient. The BCM watches that load, so the in-range element keeps BCM load detection clean and prevents nuisance DTCs.

Backing plate and coating

The backing plate is high-impact, UV-stabilized ABS rated from -40°C to +105°C, with snap-fit tabs that replicate OEM retention geometry. It clips in without adhesive, which removes the mount-failure mode common on glue-only economy glass.

The reflective layer is vacuum-deposited chromium with MIL-C-675C Type II anodic sealing, over 85% reflectance across the 400–700nm band. The polymer is RoHS 3 (EU 2025/1194) compliant with zero halogen flame retardants, per 2026 EU End-of-Life Vehicle material restrictions.

DTC Mapping and Heater Diagnostics

Mirror heater faults land in the B2300 to B2385 body range, the Mirror Driver Feedback Potentiometer family. On 2026-era scan tools, watch for four codes:

• B2321, circuit open: element resistance has drifted above 50 Ω.
• B2322, short to battery: an internal element short draws more than 5A on the MIR HTR fused circuit.
• B2323, short to ground: resistance below 1 Ω, usually moisture corroding the spade terminals at the mirror housing pivot.
• U0144, lost communication with BCM "D": can cascade when repeated B232x overcurrent events make the BCM shut the heater driver down.

These are B-codes, so they never light the check engine lamp. On 2025–2026 models with BCM firmware after calibration 89663-XXXXX, a persistent B2321 or B2323 stores silently and can post a "Check Mirror System" message on the multi-information display. Read the codes with Techstream v18.x or any SAE J2534-2 pass-through tool.

Heater Circuit Topology and CAN-bus 3.0

Toyota runs one mirror heater design across these platforms. On the CT200h, ES300h, GS450h, and LS460 the path is identical: ignition-switched 12V feeds the 10A MIR HTR fuse, then a relay triggered by the rear defogger switch, then a parallel feed to both mirror elements, then chassis ground. The shared 87961-76020 and 87931-76020 part numbers across these models point to the same circuit.

The Koeep element is a purely passive load: no CAN-bus termination, no LIN-bus addressing, no data-line traffic. It works with 2025+ Toyota/Lexus CAN-bus 3.0 (CAN-FD, 5 Mbps) body networks without BCM reconfiguration, and the heater stays on its fused hardwired circuit, isolated from bus-controlled electronics.

Installation and Verification

Installation is mechanical: unclip the broken glass, transfer the two-pin connector, and snap the new assembly into the housing on the OEM-geometry tabs. After that, run this sequence:

1. Measure heater resistance at the mirror connector. Target: 6.5–8.0 Ω.
2. Activate the rear defogger and confirm the mirror surface reaches +35°C within 90 seconds at 0°C ambient, per the Toyota TS-4600G protocol.
3. Scan with Techstream and clear any historical B232x entries.
4. Run a 10-cycle defogger on/off test to confirm the BCM load monitor logs no false open-circuit fault.

On 2013–2017 LS460 models, intermittent defrost usually traces back to a micro-fracture in the silver-palladium trace (a faint hairline under magnification), corrosion at the two-pin spade connector where the harness enters the door shell, or a degrading MIR HTR relay in the under-hood junction block.

A resistance reading that flips between 6–8 Ω and open confirms the fractured trace. The Koeep heated mirror glass assembly is the drop-in fix, with the backing plate pre-bonded.

Service Life and Fleet Size

Under normal conditions (up to 1,500 heating cycles per year, ambient -30°C to +40°C), the glass is projected for 7–10 years of service, running 2026 through 2033 with a design target to 2036. The Ag-Pd element is cycle-tested past 15,000 on/off events at 12.8V. J.D. Power's 2025 U.S. Vehicle Dependability Study puts average Lexus ownership at 8.2 years, so one part covers a typical first owner.

The addressable fleet is large: seven variants across the 2011–2018 model years, an estimated 1.2 million vehicles on North American roads as of 2026, per IHS Markit VIO data.

More Heated Mirrors at Koeep

Koeep carries heated mirror assemblies for other makes too. For a European sedan, the Power Heated Mirror Driver Left LH for 96-99 Mercedes E-Class w/Memory keeps the memory function on the W210 driver side.

For GM trucks, the Chrome Mirror for 07-13 Chevy GMC Power-Fold Driver Side Heated Memory Signal bundles power fold, heat, memory, and the turn signal in one housing. Its buying notes pair with the Complete Guide to Driver Side Power Heated Tow Mirror for 2000-2002 Chevy GMC Black Smooth.

Beyond mirrors, the Body Parts catalog covers bumpers and other exterior components across makes and model years.

Ordering and Support

To order, use the Koeep product page and select your side and model year. Fleet or bulk buyers can submit the Request for Quote form. If fitment is unclear before purchase, message support@koeep.com or the team on WhatsApp and they will check your model against the cross-reference list.

Frequently Asked Questions