REDWOOD CITY -- A California Highway Patrol mechanic in San Francisco embezzled about $17,700 in taxpayer money by billing his employer for repairs that were never made, a prosecutor said.

Lester Frank Gutierrez, 46, of Daly City pleaded not guilty Tuesday in San Mateo County Superior Court to one count each of felony embezzlement and grand theft, District Attorney Steve Wagstaffe said. Gutierrez's job was to maintain and service the fleet of cars at the San Francisco CHP division.

Prosecutors say Gutierrez conspired with the body shop manager at Serramonte Ford in Colma from August 2011 to September 2012 to bill the CHP for $16,056 in phony fixes. Gutierrez also allegedly billed the agency for $1,700 in car parts that he took for himself.

The CHP is still investigating the manager, and he has not been charged, Wagstaffe said.

Prosecutors say the scam began to unravel when CHP officials realized they were being billed for parts that couldn't be used on their type of vehicles. An audit later revealed the billing for allegedly fake repairs.

Gutierrez is out of jail on $75,000 bail and is due back in court July 24.

Contact Joshua Melvin at 650-348-4335. Follow him at Twitter.com/melvinreport.