
TROUBLESHOOTING (Cont'd)
Symptom | Possible causes | Checks and corrections | Page
No blower control | Defective water temperature relay | Check for open | AC-9
| Defective heat mode switch | Check for short | AC-9
| Defective water temperature switch | Check for short | AC-20
| Defective Hi-speed relay | Check for short | AC-9
| Defective wiring connection | Check and repair | AC-9
| Defective vacuum circuit | Check for leak and repair | AC-16
Interior temperature does not lower | Blown fuse or circuit breaker | Replace | AC-9
| Defective magnetic clutch | Check and repair | AC-23
| Defective compressor | Check and repair | AC-23
| Defective pressure switch | Replace | AC-9
| Defective expansion valve | Replace | AC-4
| Defective EPR | Replace | AC-4
| Insufficient refrigerant in system | Check and charge refrigeration system | AC-11
| Defective A/C switch | Check for short or open | AC-9
| Defective temperature sensors (in-car sensor, ambient sensor) | Check for short | AC-19
| Defective rheostat | Check for short | AC-9
| Defective power servo unit | Check operation | AC-17
| Defective DVV | Check operation | AC-20
| Defective amplifier | Check operation |
| Defective condenser motor | Check operation | AC-21
| Defective A/C relay | Check operation | AC-9
| Defective wiring connection | Check and repair | AC-9
| Defective vacuum circuit | Check for leak and repair | AC-16
Interior temperature does not rise | Defective water valve | Check operation |
| Defective temperature sensors (in-car sensor, ambient sensor) | Check for open | AC-19
| Defective rheostat | Check for open | AC-9
| Defective power servo unit | Check operation | AC-17
| Defective DVV | Check operation | AC-20
| Defective amplifier | Check operation |
| Defective wiring connection | Check and repair | AC-9
| Defective vacuum circuit | Check for leak and repair | AC-16
Unstable operation (hunting) | Defective vacuum circuit | Check for leak and repair | AC-16
| Poor connection of rheostat | Check and repair | AC-9
| Defective power servo unit | Check operation | AC-17
| Defective DVV | Check operation | AC-20
| Defective amplifier | Check operation |
| Poor connection in wire | Check and repair | AC-9
Improper shifting of dampers | Misadjusted control lever or rod | Check and repair | AC-9
| Disconnected control wire | Check and repair | AC-19
| Defective dampers | Check and repair |