[bhonstl]

Hello. Seeking some help. I am the owner of a 2002 STS. I am hoping you can help me with a situation involving my front electric struts. After replacing them with passive air struts, I have no place to plug the remaining wires and I am now getting a message that says. “Service Suspension Sys/Limit Speed to 90 MPH” along with 2 DTC codes C0579 and C0584.

I searched the forums and found out about something called the resistor trick using 4.7 kohm, ½ watt resistors. I took 2 pieces of wire and soldered them to both ends of the resistor. I did this twice with both resistors. I cut off the wires harnesses that were connected to the electric struts, stripped the wires and butt spliced the resistor/wires to the strut wires. (One on each side of the car) The message has not gone away, which tells me I did something wrong.

Any idea what I did wrong? Am I supposed to attach the wires and then reset the DTC computer? Or am I missing a step. Please. Any help that you can give me would be awesome.

Hello. Seeking some help. I am the owner of a 2002 STS. I am hoping you can help me with a situation involving my front electric struts. After replacing them with passive air struts, I have no place to plug the remaining wires and I am now getting a message that says. “Service Suspension Sys/Limit Speed to 90 MPH” along with 2 DTC codes C0579 and C0584.

I searched the forums and found out about something called the resistor trick using 4.7 kohm, ½ watt resistors. I took 2 pieces of wire and soldered them to both ends of the resistor. I did this twice with both resistors. I cut off the wires harnesses that were connected to the electric struts, stripped the wires and butt spliced the resistor/wires to the strut wires. (One on each side of the car) The message has not gone away, which tells me I did something wrong.

Any idea what I did wrong? Am I supposed to attach the wires and then reset the DTC computer? Or am I missing a step. Please. Any help that you can give me would be awesome.

My car was built 04/02 so I think it’s the F55 Magna-Ride system.

Threads merged from new model "STS".

 

[MoistCabbage]

Wrong forum. This is for the RWD STSs, not Sevilles.

No air involved with the front suspension.

The 4.7K ohm resistors are for F45 equipped cars. What is the build date of your car (on the label on the drivers door). If it's 2/15/02 or later, you have F55/MagneRide. Different resistor value required.

 

[Submariner409]

Your car has the Magnetic Ride Control system (RPO F55) and the suspension, front to rear, is now seriously unbalanced for control and ride. Too bad that you did not keep the factory suspension and controls, cost be damned.

The resistor for F55 MRC struts/shocks (no air involved in the struts OR shocks for ride control) is a 2 - 4 Ohm 5 or 10 Watt wirewound or metal film power resistor. The control current for the MRC system is considerably higher than the older CVRSS and has different electrical values. You can find the original connector for the strut pigtail to the body harness, either cut and crimp the resistor to those 2 wires or plug the resistor into the body connecter - same as plugging a bent paper clip into a wall socket. Insulate and waterproof well.

The only "air" involved in our cars is the height control system and air bladders on the rear shocks. No air is used in suspension control.

 

[basscatt]

here ya go -

F55 to PASSIVE
http://www.cadillacforums.com/forum...resistor-bypass-f55-magneic-ride-control.html

radio shack 1.0 ohm - 10 watt resistor -
# 271-131 - 2 per pack -
you need 2 per strut/shock - wired in series

 

[Jays03dsg]

I did the same thing to mine and it still gave same message on my DIC. Mine is a 2002, but the build date is 10/01 on the door sticker. I then checked the RPO sticker on my spare just to make sure and it's an F45 setup.

 

[Submariner409]

For your F45 car the resistors are 1/2 or 1 watt 4.7K Ohm (4700 Ohm) types.

For a F55 car the value is about 2 Ohms, but use a 5 or 10 watt power resistor due to the current involved.

Either cut the strut/shock plug off the old strut/shock pigtail and solder the resistors to the bared wire ends, insulate well and plug the pigtails back into the body harness or bend the resistor leads into a U and insert into the body harness connector.

Here's your F45 strut/shock connector schematic. Zoom in. The pigtail suspension damper connectors are shown as >>

 

[Jays03dsg]

For your F45 car the resistors are 1/2 or 1 watt 4.7K Ohm (4700 Ohm) types. For a F55 car the value is about 2 Ohms, but use a 5 or 10 watt power resistor due to the current involved. Either cut the strut/shock plug off the old strut/shock pigtail and solder the resistors to the bared wire ends, insulate well and plug the pigtails back into the body harness or bend the resistor leads into a U and insert into the body harness connector. Here's your F45 strut/shock connector schematic. Zoom in. The pigtail suspension damper connectors are shown as >>

The picture represnts the setup i did for each side, however i must have done it wrong because it only worked for one cycle. I have the 1/2 watt 4.7k ohm resistors, but i only used 1 resistor per shock and bent it in a "U" position with one lead from the resistor soldered to one wire from the old plug, and the other lead soldered to the other side. Is this correct way or should i have used 2 resistors? Please excuse my fancy artwork as i did not think it would be necessary to draw the solder, electrical tape, heat shrink.

 

[MoistCabbage]

That's the correct way to do it. One resistor per shock/strut.

 

[Submariner409]

............. but, from his drawing, he screwed up and jumped the brake wear sensor pigtail, not the strut connector.

If you want to "fool" a worn out brake wear sensor you simply solder the bared ends together. The sensor is a sacrificial foil puck that wears down as the pads get thinner - at some point the circuit opens and the brake warning comes on.

In cars so equipped, you can have three chassis wires going out to the front and rear suspension and hubs - a brake wear sensor at each wheel caliper (replaceable), a wheel speed sensor connector at the hub center and an active suspension control wire that connects to the bottom of a strut or the top of a shock - the "suspension dampers" in the schematic - that's the wire that you jump.

 

[Jays03dsg]

Why would i still be receiving the “Service Suspension Sys/Limit Speed to 90 MPH” message on my DIC? Could it be a lack of connection between the resistor/solder/wire? I did use the stock plug/pigtails. I ordered the break wear sensor (as i have in the picture) but i haven't tried them yet, could that be a possibility? Also, i just now realized that this is for a front strut replacement, Will this work for the rear suspension (as that is what my issue is)?

 

[Submariner409]

It won't work because you apparently jumped the brake wear sensor(s), not the suspension damper control wire. Please read my post. Brake wear sensors come from the inner side of the brake caliper.

The strut control wire connects at the bottom of the strut. The F45 wire connects at the bottom of the shock. F55 connects at the top in the trunk.

EDIT: Here - click to enlarge - use your browser <-- to back out

 

[Jays03dsg]

It won't work because you apparently jumped the brake wear sensor(s), not the suspension damper control wire. Please read my post. Brake wear sensors come from the inner side of the brake caliper.The strut control wire connects at the bottom of the strut. The F45 wire connects at the bottom of the shock. F55 connects at the top in the trunk.EDIT: Here - click to enlarge - use your browser

Based on the image of the F45 suspension, I currently have the resistor attached to that wire where it was suppose to connect to the strut. Here is the picture from underneath.