FX3 upgrade from 1990 to 1992 - ZR-1 Net Registry Forums

sevensixers · 5 Days Ago

I upgraded my fx3 shocks and control module from 1990 to 1992 setup. I have brand new shocks and a used 1992 control module. I keep getting fault codes 14, 31, 32, 33? I have removed the actuators to verify operation and they do work when the ignition is turned on, so they are trying to find the end stops. I checked that the shock gear is 5mm higher than the mounting ring on top of the shocks. The shock gears rotate freely with no binding. I tried swapping actuators around and no change. I?ve tried to clear the faults by grounding the C pin on the ALDL plug. Does anyone have any ideas of what else to try ? I thought it would be a direct swap with no issues, but I should have known better !!! Any help to get these faults cleared would be greatly appreciated !!! Thanks gang !!!

-=Jeff=- · 14 Hours Ago

Here are the errors.

14 = Right Front time out
31 = Left Front out of position
32 = Right Front out of position
33 = Left Rear out of position

Looks like the right rear works. Are the gears tight on the shocks? i have heard that could cause an issue. I have also had issues with the set height, how do you know that the shock gear is in the actuator?

secondchance · 6 Hours Ago

On my car, a 94, I was tripping code for front. Upon careful examination, I noticed OEM set up has rubber bushing between the top of the shock to underside of the steel bracket and another rubber bushing on top of the bracket to metal plate below metal cup. The lower rubber bushings had collapsed due to age resulting in the entire assembly being pushed up and the shock pinions were too high binding inside the actuator. Been awhile but I think I replaced lower bushing (under the bracket) with a new polyurethane version but kept OEM rubber bushing because polyurethane would raise the cup too high. Shop manual section 3G-20, figure 3 illustrates top of the metal cup to top of shock pinion to be 4.5 mm. Excessive deviation can either bind the mechanism (more than 4.5 mm) or pinion not engaging the planetary gear in the actuator (less than 4.5 mm).
As for the rear, I would make sure the shock gear (pinion) is good and actuator is functioning properly.
One more thing, at times rotation of shock gear are bit stiff and may require light lubrication to encourage easier rotation to trigger codes.

5 Days Ago	#1
sevensixers Join Date: Jun 2022 Location: Delaware Posts: 10	FX3 upgrade from 1990 to 1992 I upgraded my fx3 shocks and control module from 1990 to 1992 setup. I have brand new shocks and a used 1992 control module. I keep getting fault codes 14, 31, 32, 33? I have removed the actuators to verify operation and they do work when the ignition is turned on, so they are trying to find the end stops. I checked that the shock gear is 5mm higher than the mounting ring on top of the shocks. The shock gears rotate freely with no binding. I tried swapping actuators around and no change. I?ve tried to clear the faults by grounding the C pin on the ALDL plug. Does anyone have any ideas of what else to try ? I thought it would be a direct swap with no issues, but I should have known better !!! Any help to get these faults cleared would be greatly appreciated !!! Thanks gang !!!

14 Hours Ago	#2
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,155	Re: FX3 upgrade from 1990 to 1992 Here are the errors. 14 = Right Front time out 31 = Left Front out of position 32 = Right Front out of position 33 = Left Rear out of position Looks like the right rear works. Are the gears tight on the shocks? i have heard that could cause an issue. I have also had issues with the set height, how do you know that the shock gear is in the actuator? __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - Flowmaster Cats - Borla Catback Late Model IH - Plenum Coilovers - 4.10s Custom Interior NCM Lifetime Member #978

6 Hours Ago	#3
secondchance Join Date: Aug 2006 Location: McLean, VA Posts: 3,715	Re: FX3 upgrade from 1990 to 1992 On my car, a 94, I was tripping code for front. Upon careful examination, I noticed OEM set up has rubber bushing between the top of the shock to underside of the steel bracket and another rubber bushing on top of the bracket to metal plate below metal cup. The lower rubber bushings had collapsed due to age resulting in the entire assembly being pushed up and the shock pinions were too high binding inside the actuator. Been awhile but I think I replaced lower bushing (under the bracket) with a new polyurethane version but kept OEM rubber bushing because polyurethane would raise the cup too high. Shop manual section 3G-20, figure 3 illustrates top of the metal cup to top of shock pinion to be 4.5 mm. Excessive deviation can either bind the mechanism (more than 4.5 mm) or pinion not engaging the planetary gear in the actuator (less than 4.5 mm). As for the rear, I would make sure the shock gear (pinion) is good and actuator is functioning properly. One more thing, at times rotation of shock gear are bit stiff and may require light lubrication to encourage easier rotation to trigger codes.