E67 ECM in 98 C5
#1
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Hey all, helping a friend with a customer's 98 C5 in his shop.. The car has a GM LSX motor in it and when the install was done (probably 10+ years ago) the shop that did the install used an E67 ecm in it. They also installed a racepak IQ3 dash display as well. Big problem is the AC does not work, haven't dug into it too deep to see where each wire is ran for the pressure switch or anything else. My concern though is if the serial signal wire from the star connector from the hvac module can be landed on Pin 16 (connector X1) of the E67 and if it will recognize the signal, sending the relay its trigger. @NicD maybe you have an idea?
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LilJayV10 (10-05-2023)
#4
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The E67s were the only Gen4 controllers that actually had a class 2 serial data bus without needing a BCM for translation. I have always heard that ALL of the Gen4 ECMs don't use the same IDs and messaging as the older Gen3 ECMs, but I've never personally looked into it and actually looked at the traffic.
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02EBC5Z06 (10-05-2023)
#5
TECH Senior Member
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The E67s were the only Gen4 controllers that actually had a class 2 serial data bus without needing a BCM for translation. I have always heard that ALL of the Gen4 ECMs don't use the same IDs and messaging as the older Gen3 ECMs, but I've never personally looked into it and actually looked at the traffic.
I do know of a couple of Gen3 trucks (03-07 style) that have had an E67 swap done and from what I am told, they used a TBSS operating system. The only thing that did not work was the gear range selector on the cluster. But as far as I know, none of them tried the 06-07 8.1 Gas cluster that was used with the Allison 6 speed.
In the Trucks, the E67 swap was done to allow use of the newer 6 speed.
Both the 03-07 and the TBSS operating system use the class 2 data bus.
Here is an 06 truck with a E67 and 6L90 swap
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