Is there a pin-compatible replacement for A1251H-6P?

There is no confirmed pin-compatible replacement without verifying mechanical drawings. While the HC-1.25-6Y is a strong candidate, connector 'pin compatibility' includes the physical housing shape, locking, and keying, which must be checked from the datasheet.

What risks should I check before replacing A1251H-6P?

The main risk is mechanical mismatch. Check the datasheet drawings for dimensions, locking tabs, and keying to ensure the replacement housing will securely connect to your PCB header. Also, verify material and temperature ratings if your application operates in harsh environments.

A1251H-6P Alternatives, Datasheet & Cross Reference | CJT

Finding a substitute for the CJT A1251H-6P 6-pin housing involves matching the 1.25mm pitch and electrical ratings. The main challenge is ensuring mechanical compatibility with the mating header, which requires careful datasheet review.

AI replacement insight

Package riskhigh

Mechanical fit, keying, and locking features are not verified and are critical for connectors.

Electrical risklow

Key electrical ratings like pitch, voltage, and current are common and easily matched.

Can it be replaced directly?

No guaranteed drop-in replacement has been confirmed. The HC-1.25-6Y is a strong candidate but you must verify its mechanical dimensions and locking features against the A1251H-6P datasheet to ensure compatibility.

Best replacement path

The HCTL HC-1.25-6Y is the most promising alternative, sharing key specs, but requires mechanical verification. For a system-level change, the JST GHR-06V-S is a common option but requires replacing the mating header as well.

Main risk

The primary risk is mechanical incompatibility. Connector housings have precise dimensions, keying, and locking mechanisms that must match the mating header. An incorrect fit can lead to unreliable connections or assembly failure.

Recommended alternatives

A strong functional match with identical pitch, position count, and ratings; requires mechanical verification.

View details

Alternative comparison matrix

Feature / factor	A1251H-6P	HC-1.25-6Y	GHR-06V-S	Compatibility / risk
Pinout	6	6	6	6 — Positions match.; GHR-06V-S: Positions match.
Pitch	1.25mm	1.25mm	1.25mm	1.25mm — Pitch matches.; GHR-06V-S: Pitch matches.
Package	Housing	1.25mm Pitch Housing	-	1.25mm Pitch Housing — Functionally a housing, but mechanical fit requires datasheet verification.
Voltage Current	1A / 125V	1A / 125V	-	1A / 125V — Ratings match.
Material	Nylon 66	Nylon66	PBT	Nylon66 / PBT — Material and flammability rating match.; GHR-06V-S: Different housing material.
Family	CJT A1251 Series	-	JST GH Series	JST GH Series — Different connector family, will not mate with target's header.
Temperature	Not specified, assumed wider	-	-25°C to +85°C	-25°C to +85°C — Candidate has a narrower operating temperature range.

Application & sourcing insights

Questions & answers

The best alternative appears to be the HCTL HC-1.25-6Y, which has the same pitch, pin count, and electrical ratings. However, you must verify the mechanical drawings to ensure it will mate correctly with your existing header.