2003 toyota matrix. i do not getting any clicking when i turn the key. just a electrical hum sound. I thought it was the battery. it would not hold a charge. I replaced the battery and same issue.

SOURCE: 1994 Toyota Camry 4 cylinder Starting problems

your starter is bad.... the two contacts inside the solinoid are worn out only way to fix is replace the unit as a whole bet ya you get click click click then my start.. bet my life on this one been fixin toyotas for 20+ years

SOURCE: Ignition and/or starter problem.

Immobilizer armed its self

SOURCE: 95 Geo Prizm Lsi will not start

95 prizms are known for starter problems if they last 2 years you are lucky..They just get way to hot where they are......And are a pain to replace....

SOURCE: Doesn't start- Thought starter was bad replaced

The ignition switch attached to the column is probally bad, check the small wire to the sloenoid for battery when the key is turned to the start postion, if no battery, your not getting power from the ignition switch to the starter solenoid.

SOURCE: 2003 BMW 530i won't start; mechanical hum, but no clicking sound

my 530i are 203 and problem was iwash the car with watter and starting problem no start all light is vuzible