P21DD (PCM) - Reductant Heater A Current Too Low
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DTC DESCRIPTION P21DD (PCM) - REDUCTANT HEATER A CURRENT TOO LOW
| Description: This DTC sets when the glow plug control module (GPCM) detects insufficient current draw from the reductant tank heater. | |||
Possible Causes:
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| Diagnostic Aids: The presence of this DTC may indicate the vehicle is operating in derate mode and may experience a loss of power. After repair, the vehicle may still display a system warning message. Drive the vehicle until the system warning message has cleared from the instrument cluster message center. | |||
| Application | Key On Engine Off | Key On Engine Running | Continuous Memory |
| All | GO to PINPOINT TEST RH . | ||