X - Testing Notes
DESCRIPTIONConstant Control Relay Module
The Constant Control Relay Module (CCRM) interfaces with the Electronic Engine Controls (EEC) system to provide control for the cooling fan, A/C clutch and the fuel pump. The CCRM also contains the EEC power relay which provides Vehicle Battery Power (VPWR) to the Powertrain Control Module (PCM) and EEC-IV system.
Dual and Single Function A/C Pressure Switch (ACPSW)
The ACPSW is used on some applications for additional A/C system pressure control and is also known as the refrigerant containment switch. For additional information, refer to Heating and Air Conditioning.
NOTE: You should enter this Pinpoint Test only when directed here from Diagnostic Routines, or from Pinpoint Tests C, PA, or PB.
REMEMBER: To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault:
- Fuel system
- A/C system
- Fuel Contamination
- Starting/charging system
This Pinpoint Test is intended to diagnose only the following:
- Constant Control Relay Module (CCRM).
- Electronic Engine Controls (EEC) Power Relay
- Low Fan Control (LFC) Relay
- High Fan Control (HFC) Relay
- Wide Open Throttle A/C Cut-Off (WAC) Relay
- Fuel Pump (FP)
- Pusher Fan Control Relay
- Harness circuits: B+, KPWR, PWR GND, FP, LFP, HFP, FC, LFC, HFC, PFC, A/C, ACCS, ACPSW, WAC
- Powertrain Control Module (PCM) (12A650)