DIAG GOLDEngineered reference, not chat — free forever
The reference portals: the charts a shop keeps open on the bench. Built like instruments, verified like paid work.
Every manifold reading decoded
A/C Gauge Playbook
Both low, both high, needles converging, low side in vacuum — visual gauge charts with causes ranked and next checks. Tap any scenario to enlarge at the fender.
10 scenariosOpen the playbook →
Meter values · scope patterns · U-codes
CAN Bus Playbook
60Ω vs 120Ω vs dead short, every CAN-H/CAN-L signature, the DLC pin map, U-code pattern reading — plus per-make network maps: buses, gateways, what breaks.
30 make network mapsOpen the playbook →
AI Diagnostic Engine
Enter multiple DTC codes or describe symptoms for probabilistic diagnosis with ranked causes.
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TSBs Indexed
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How the Diagnostic Engine Works
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2
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View real-world fixes submitted by technicians, ranked by confirmation count.
3
Check TSBs & Recalls
Access related Technical Service Bulletins and active recalls from NHTSA.
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