No Crank No Start with Dim Lights - Seized Starter and Blown Relay
Electricaladvanced✓ OP Confirmed
Problem
1988 Supra MKIII would not crank or start. Turning the key to start produced no clicking from the starter relay and caused all interior/dash lights to dim or shut off. The car also would not roll freely on the ground despite the transmission being in neutral.
No crank when turning key to start positionNo clicking sound from passenger side kick panel relayAll interior lights, dash lights dim or shut off when key turned to startCar would not roll or be pushed on the ground while in neutralFull electrical power to accessories (radio, pop-up headlights, dash lights) when not crankingHard/weak cranking noticed a few days before complete failureBrake lights not working (related but separate issue)
Root Cause
The original 1988 factory Denso starter motor seized in the engaged position, locking against the flywheel. This also blew the starter relay located in the passenger side kick panel. The combination of the seized starter and blown relay caused the no-crank, no-click, lights-dimming symptoms.
Confidence
Moderate confidence — Original poster confirmed this resolved the issue
View Original Thread →Posted March 2025 on SupraForums.com