With Heater System - Front

- CHECK that either the A/C MAXI FUSE or the HTR A/C (Fuse 12) is not open. If either fuse is open, LOCATE and REPAIR source of overload and REPLACE the Fuse(s).
- CHECK that Grounds G100, G104, G200 and G301 are clean and tight.
- CHECK that Blower Motor Resistor and Relay Pack is properly mated to its connector.
- Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove GOOD in a Continuity/Voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by' monitoring for a voltage drop with the system operational (under load).
- CHECK for proper installation of aftermarket electronic equipment which may affect the integrity of other systems (Refer to Troubleshooting Procedures). Diagnostic Aids