What P1600 means
This is a diagnostic trouble code (DTC) reported by your vehicle's onboard OBD-II system when a specific fault is detected in the powertrain.
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P1600:
| BUICK | PCM Battery |
| CADILLAC | PCM Battery |
| CHEVY | PCM Battery |
| CHRYSLER | Serial Communication Link Malfunction; Loss Of KAM Power,Cricuit Open; Loss of KAM Power - Open Circuit; Engine control module (ECM) - external access RAM error |
| FORD | Loss of KAM Power; Open Circuit |
| GEO | PCM Battery Circuit Fault |
| GM | PCM Battery; PCM Battery Malfunction |
| GMC | PCM Battery |
| JAGUAR | Loss Of Kam Power Circuit Open |
| LEXUS | ECM BATT Malfunction |
| LINCOLN | Loss of KAM Power Open Circuit |
| MAZDA | Loss Of KAM Power Circuit Open |
| MERCURY | Loss of KAM Power Open Circuit |
| MITSUBISHI | Loss of KAM Power; Open Circuit; PCM/TCM serial communication link circuit fault |
| NISSAN | Loss of KAM Power; Open Circuit |
| OLDSMOBILE | PCM Battery |
| OTHER | Loss of KAM Power; Open Circuit |
| SATURN | PCM Battery |
| SUZUKI | PCM TCM Serial Communication Circuit Fault |
| TOYOTA | ECM BATT Malfunction |
| VOLKSWAGEN | TCM Internal Watchdog Operation; Power Supply (B+) Terminal 15 Low Voltage |
Read this code on your own car
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