Diagnostic Aids
WARNING: This page is about a different car, the 2022 Cadillac CT5. However, it is still accessible from the selected car via links, so may be relevant.
- short to B+ or an open in the KR73 Ignition Main Relay coil control circuit can cause a DTC to set.
- A open or high resistance in the KR73 Ignition Main Relay coil ground circuit can cause a DTC to set.
- Stuck or open contacts in the KR73 Ignition Main Relay can cause a DTC to set.
- The DTC can set due to a sticking relay or there is short to B+ on the fused circuits that are supplied by the relay output control circuit.
- A short to voltage in the ignition circuit will keep the vehicle modules awake, which can drain the vehicle's battery.
- The last 2 digits of the circuit number are significant in identifying its power and/or ground function.
- Circuits ending in 42 are primary fused B+ circuits (generally the first fuse in the circuit after the battery)
- Circuits ending in 40 are secondary fused circuits (generally fuses in a fuse block after the primary circuit)
- Circuits ending in 39 and 41 are ignition voltage circuits.
- Circuits ending in 50 are grounds.
- Circuits ending in 51 are low reference (ground).
NOTE:
The circuit numbers listed below are a general overview and may not reflect the schematics for this document.