SINOTRUK Sitrak EV Electric Coolant Pump 712W61942-0776/4 (Thermal Management Auxiliary Water Pump)

## What this pump does

Electric auxiliary coolant pump for the thermal management circuit on SINOTRUK Sitrak new-energy (EV) trucks. It moves coolant through the battery, motor and air-conditioning heat exchanger loops on its own — no belt, no dependence on engine speed — so the controller can hold flow at low speed or with the truck standing still.

That is why a failed pump does not show up as an engine overheating problem. It shows up as weak cabin cooling, a battery or motor over-temperature warning and a power derate.

## Nameplate data — match it before you order

| Line | Value |
|—|—|
| Part number on label | **712W61942-0776/4** |
| Barcode | 0232399452250120000563 |
| Cast marking | MRT DB001 VISU |
| Stamped numbers | 100846 · 250103 000453 |
| Label | 原厂部件 OEM PARTS with the SINOTRUK triangle mark |

Any one of those lines is enough for us to confirm the pump you need.

## What you see on the body

– Aluminium pump housing with three mounting lugs — mount on the original bolts and do not over-torque, the plastic side of the housing cracks first.
– One hose spigot on the top elbow, the outlet on the opposite side; both take the standard push-on hose and spring clamp.
– Sealed electrical connector with a latch. Release the latch before pulling — never pull on the harness.

## Failure symptoms

| Symptom | What it usually means |
|—|—|
| Cabin AC weak, or no heat at idle | pump not running, only residual circulation |
| Battery or motor over-temperature warning, power derate | the loop lost flow |
| Outlet hose stays cold while the inlet is hot | impeller not turning |
| No self-test hum at ignition on | open circuit, blown fuse or dead pump |
| Pump fault code stored in the controller | check supply and ground before you replace it |

## Fitting notes

1. Drain the loop and refill with the coolant specified for the vehicle. Do not top up with water on these circuits.
2. Never run the pump dry — a few seconds is enough to score the impeller.
3. Bleed the circuit: trigger the pump through the diagnostic routine, top up, repeat until no bubbles come back.
4. Check the connector pins for corrosion and the seal for cracks. A corroded pin is the usual reason a new pump fails again a month later.
5. Clear the old fault code and confirm flow before the truck goes back on the road.

## Fitment

SINOTRUK Sitrak new-energy trucks (C7H / C5H EV versions), thermal management and air-conditioning coolant circuit. Other 712W-series new-energy parts use the same numbering family — send your VIN and we will confirm the match before shipping.

## Ordering

Minimum order 1 piece. Stock leaves within 2–3 working days, with photos of the actual unit and the packing before shipment, then the tracking number. Air express for urgent orders; sea or rail for bulk.