Fault Message:

R CH B LOW TENSION IGNITN[1] RNG MA

Fault Code:

7327417RBR

Associated CAS:

None

There is an open or short circuit in the low-tension circuit of Ignition System 1. The fault is found between the Engine Electronic Controller (EEC) and the Ignition Unit 1. The low-tension ignition circuits are continuously monitored by the Full-Authority Digital Engine-Controller (FADEC).

• Ignition Unit 1
• Right Engine Electronic Controller (EEC)
• Secondary Power Distribution Assembly (SPDA) 3 (A15)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

WARNING: Before touching the ignition system components, make sure of the conditions that follow:

• Isolate the power supply (make sure the applicable circuit breakers are open)
• After the power supply is isolated, do not touch the ignition system components before a minimum of three minutesThis must be done to make sure that the residual current decreases to a safe level. The ignition system has very high voltages which can kill.

1. Perform a visual inspection of the ignition circuit wiring. Inspect for damage and proper installation.
   NOTE: Look specially for signs of damage adjacent to clip locations.

   1. If damage or defect is found, rectify or repair as required and do close out.
   2. If no damage or defect is found, continue with next step.

2. Check if the CAS message R FADEC FAIL is displayed.

   1. If the CAS message R FADEC FAIL is displayed, troubleshoot the message first and continue with next step.
   2. If the CAS message R FADEC FAIL is not displayed, continue with next step.

3. Disconnect the EEC connector (P1046) and the ignition unit 1 connector (P1055). Perform a visual inspection of the associated wiring and EEC connector (P1046) and ignition unit 1 connector (P1055).
   NOTE: Look specially for signs of chafing adjacent to clip locations, condition of connector pins and wiring kink or strain.

   1. If defects are found, repair or rectify defects as required and do close out.
   2. If no defects are found, continue with next step.

4. Perform a continuity check as follows:

   From	To	Result
   P1055-2	P1046-30
   P1055-1	P1046-51

   1. If there is no continuity, repair defective wiring as required and do close out.
   2. If there is continuity, continue with next step.

5. Perform a insulation resistance check of the associated wiring between the EEC and the ignition unit 1 as follows:

   From	To	Resistance Value	Result
   P1046-30	Ground	20 ΜΩ or more
   P1046-51	Ground	20 ΜΩ or more

   1. If the resistance value is less than the value specified in the table of if there is a short to ground, repair defective wiring as required and do close out.
   2. If there is no continuity or resistance value is as specified in the table, continue with next step.

6. Remove the fixed cowl interface connector (2PB2). Check if there is 28 VDC as follows:

   From	To	Expected Result	Result
   2JB2-7	2JB2-8	28 VDC

   1. If there is no 28 VDC, investigate the power source for SPDA 3 and do close out.
   2. If there is 28 VDC, continue with next step.

7. Swap EEC 2 with EEC 1. Is the fault still present?

   1. If NO, replace EEC 2 and do close out.
   2. If YES, continue with next step.

8. Replace Ignition Unit 1.
9. Do close out.