2pcs MAH-112-C-4 12V 40A 5-Pin SPDT Mini ISO Automotive Relay - Plug-in 27.8x27.8mm Fuse Box Multi-Purpose

MAH-112-C-4(1.7W) 12V 40A 5-Pin SPDT Changeover Automotive RelayThis is a mini ISO style plug-in relay used for switching higher-current circuits in a vehicle fuse/relay box. Always confirm the part number and terminal layout before ordering.Key specs: 12V coil; 40A switching (max); 5-pin SPDT / 1C changeover; plug-in case 27.8×27.8mm; coil rated power 1.7W.Common uses: fuse/relay-box switching for circuits such as cooling fan, horn, lighting, A/C clutch, fuel/ACC power (varies by vehicle and relay slot).Common symptoms (not a guarantee): intermittent operation, clicking but no output, overheating relay, or the controlled circuit not turning on/off reliably.Install notes: disconnect the negative battery cable; remove the old relay straight up; compare markings and pin layout; press the new relay fully seated; then test the circuit.Fitment reminder: confirm by OE/part number MAH-112-C-4(1.7W) and the fuse/relay box label or vehicle manual. Do not substitute a 4-pin relay for a 5-pin changeover relay.

• SPEC & OE REF — MAH-112-C-4(1.7W) automotive plug-in relay: 12V coil, 40A switching (max), 5-pin SPDT / 1C changeover; plug-in case 27.8×27.8mm; coil rated power 1.7W. Mini ISO 5-pin changeover style for fuse/relay-box switching. Typical relay-controlled circuits can include radiator/condensor fan, horn, headlights/fog lights, A/C compressor clutch, fuel pump or accessory power (depends on vehicle & slot). SEO keywords: 12V 40A relay 5 pin, SPDT changeover relay, mini ISO relay, fuse box relay, fan relay, horn relay, A/C relay. Confirm fitment by the printed part number and terminal layout before purchase.
• INSTALL & LOCATION TIPS — This relay is commonly found in an under-hood fuse/relay box or an interior junction/fuse block (location varies by vehicle). Before removal, disconnect the negative battery cable and note the relay position from the fuse/relay box diagram on the cover or in your vehicle manual. Pull the old relay straight up (relay puller helps), then compare: part number marking, 5-pin SPDT changeover layout, and socket condition. A 5-pin SPDT relay is not the same as a 4-pin SPST relay—verify pin functions and do not force into the wrong cavity. After installation, press fully seated and test the related circuit; if the issue remains, inspect fuses, wiring and the load device.
• FITMENT CHECK (NO GUESSING) — Confirm fitment by OE/part number and your vehicle documentation: match the exact MAH-112-C-4(1.7W) marking on the original relay, confirm 12V 40A 5-pin SPDT changeover footprint, and verify the relay slot name/function on the fuse/relay box label or service manual. Helpful when diagnosing intermittent no-fan, no-horn, no-A/C clutch engagement, lighting or accessory-power issues caused by a weak/sticking relay (symptoms vary by circuit). Related items: mini ISO 5-pin relay socket/base, relay puller, fuse puller, relay tester, electrical contact cleaner.