A/T - 4L80E Multiple/Intermittent Trouble Codes
TECHNICAL BULLETIN # 155TRANSMISSION: 4L80-E
SUBJECT: MULTIPLE CODES
APPLICABLE: GM - ROLLS ROYCE - JAGUAR
4L80-E Multiple/Intermittent Trouble Codes
A condition of intermittent shift complaints and multiple trouble codes may be caused by the case connector connection. Remove the main connector on the left side of the transmission and look for signs of transmission fluid. Any fluid present in the connector can cause problems.
If the connector is leaking fluid, remove the internal harness. Peel the rubber boot back from the inside of the pass thru connector and clean off all oil residue. Seal the wire holes in the connector with silicone as shown.
Although this may seem to be an unconventional repair, it has been quite successful.