MQ Power DCA25USI4CAN troubleshooting: 32 symptom-cause-remedy entries from the manufacturer's own service documentation.
MQ Power DCA25USI4CAN — full specs, parts & maintenance.
| Symptom | Cause | Remedy |
|---|---|---|
| No Brakes | Brake line broken or kinked? | Repair or replace. |
| Weak Brakes or Brakes Pull to One Side | Brake lining glazed? | Reburnish or replace. |
| Weak Brakes or Brakes Pull to One Side | Trailer overloaded? | Correct weight. |
| Weak Brakes or Brakes Pull to One Side | Brake drums scored or grooved? | Machine or replace. |
| Weak Brakes or Brakes Pull to One Side | Tire pressure correct? | Inflate all tires equally. |
| Weak Brakes or Brakes Pull to One Side | Tires unmatched on the same axle? | Match tires. |
| Locking Brakes | Brake components loose, bent or broken? | Replace components. |
| Locking Brakes | Brake drums out-of-round? | Replace. |
| Noisy Brakes | System lubricated? | Lubricate. |
| Noisy Brakes | Brake components correct? | Replace and correct. |
| Dragging Brakes | Brake lining thickness incorrect or not adjusted correctly? | Install new shoes and linings. |
| Dragging Brakes | Enough brake fluid or correct fluid? | Replace rubber parts fill with dot 4 fluid. |
| Center Wear | Over inflation. | Adjust pressure to particular load per tire manufacturer. |
| Edge Wear | Under inflation. | Adjust pressure to particular load per tire manufacturer. |
| Side Wear | Loss of camber or overloading. | Make sure load does not exceed axle rating; Align wheels. |
| Toe Wear | Incorrect toe-in. | Align wheels. |
| Cupping | Out-of-balance. | Check bearing adjustment and balance tires. |
| Flat Spots | Wheel lockup and tire skidding. | Avoid sudden stops when possible and adjust brakes. |
| No Voltage Output | AC Voltmeter defective? | Check output voltage using a voltmeter. |
| No Voltage Output | Is wiring connection loose? | Check wiring and repair. |
| No Voltage Output | Is AVR defective? | Replace if necessary. |
| No Voltage Output | Defective Rotating Rectifier? | Check and replace. |
| No Voltage Output | Defective Exciter Field? | Check for approximately 17.3 ohms across J & K on CN1 |
| Low Voltage Output | Is engine speed correct? | Turn engine throttle lever to “High”. |
| Low Voltage Output | Is wiring connections loose? | Check wiring and repair. |
| Low Voltage Output | Defective AVR? | Replace if necessary. |
| High Voltage Output | Is wiring connections loose? | Check wiring and repair. |
| High Voltage Output | Defective AVR? | Replace if necessary. |
| Circuit Breaker Tripped | Short Circuit in load? | Check load and repair. |
| Circuit Breaker Tripped | Over current? | Confirm load requirements and reduce. |
| Circuit Breaker Tripped | Defective circuit breaker? | Check and replace. |
| Circuit Breaker Tripped | Over current Relay actuated? | Confirm load requirement and replace. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Brake lining glazed?; Trailer overloaded?; Brake drums scored or grooved?; Tire pressure correct?. See the table for the matching fixes.
Documented causes: AC Voltmeter defective?; Is wiring connection loose?; Is AVR defective?; Defective Rotating Rectifier?. See the table for the matching fixes.
Documented causes: Short Circuit in load?; Over current?; Defective circuit breaker?; Over current Relay actuated?. See the table for the matching fixes.