CEL When Steering Wheel turned left
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
CEL When Steering Wheel turned left
I have been chasing an electrical gremlin for about 4 weeks in a 99 FRC. It has not been in the rain (drought here in GA anyway) but in the garage.
I know I have a right front turn lamp socket with a short (new front light harness should be here tomorrow at ten) all the other grounds/harness look good - BUT...
There has not ever been a battery leak and all looks good under the battery now.
I can get a CEL flash and a stumble when I turn the wheel left with vigor and sometimes I get a CEL flash and stumble when I hit a bump - especially when turning left. Lately, I have gotten code C1278 and "Service Traction Control" with some of these "stumbles". We replaced three out of 4 wheel bearings last weekend due to play (this is a NASA TT car).
The dash seems to lose power for a second and the Tach/Speedo do a "mad sweep" for a second before returning to normal - car loses power and then recovers. Resets the avg MPG also
Based on a RAFT tip we will check the IPC ground tomorrow also.
Could this be a steering sensor?
Any tips or advice greatly needed.
I know I have a right front turn lamp socket with a short (new front light harness should be here tomorrow at ten) all the other grounds/harness look good - BUT...
There has not ever been a battery leak and all looks good under the battery now.
I can get a CEL flash and a stumble when I turn the wheel left with vigor and sometimes I get a CEL flash and stumble when I hit a bump - especially when turning left. Lately, I have gotten code C1278 and "Service Traction Control" with some of these "stumbles". We replaced three out of 4 wheel bearings last weekend due to play (this is a NASA TT car).
The dash seems to lose power for a second and the Tach/Speedo do a "mad sweep" for a second before returning to normal - car loses power and then recovers. Resets the avg MPG also
Based on a RAFT tip we will check the IPC ground tomorrow also.
Could this be a steering sensor?
Any tips or advice greatly needed.
Racer
Joined: Sep 2006
Posts: 464
Likes: 2
From: New Bern NC
I would guess you have a bad ground or maybe even a bad battery or battery connection. Usually when I hear about electrical problems when you hit a bump or jerk the wheel I think loose connection. Usually its a ground bolt or battery lead that has come loose and from vibrations and when you hit a bump or something the wire jiggles and opens or closes the circuit.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Battery connections are always a great FREE place to start. Remove the cables, inspect them, clean them and TORQUE them on the battery to the correct 11 ft/lbs.
Another area of CONCERN is the pass and drivers door wiring harnesses. Pop the accordion tube off on both ends,,pull the connectors out of the door frame pocketand examine the connectors for bare wires and loose pins.
What DTCs are you seeing when the issue happens??? Please list them ALL!!!!
As always, check your chassis grounds.
(Thats FREE by the way!!)
Let us know if this advice helps you!
BC
Another area of CONCERN is the pass and drivers door wiring harnesses. Pop the accordion tube off on both ends,,pull the connectors out of the door frame pocketand examine the connectors for bare wires and loose pins.
What DTCs are you seeing when the issue happens??? Please list them ALL!!!!
As always, check your chassis grounds.
(Thats FREE by the way!!)Let us know if this advice helps you!
BC
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
I checked the battery (it is an older red top Optima) first thing. Using my handy multi-meter I checked at the fuse boxes (per the sticky above) - reads a steady 12.22 no matter what I do with the battery or the cables.
We did notice a "hiss" sound around the battery after the car was shut off...I had it tested about 8 weeks back when I fired off the new engine. It tested fine then.
I checked the underhood grounds - is there an easy way to get those bad boys apart? They were basically OK - nothing even close to the photos in the thread.
I will be checking the rest of the grounds as I can access them...
I have had
C1278
U1016
U1094 (a lot!)
U1064
B1001
--516 the VSS code - it, and its wire, checks fine.
Both sets of O2 sensors - I think I solved them
At the moment the flickering CEL does not set a code - just stumbles the car...
The BCM is dry and clean...
I will check the doors...
I really did do all the "free" things first
As I get "fresh codes" I will report
We did notice a "hiss" sound around the battery after the car was shut off...I had it tested about 8 weeks back when I fired off the new engine. It tested fine then.
I checked the underhood grounds - is there an easy way to get those bad boys apart? They were basically OK - nothing even close to the photos in the thread.
I will be checking the rest of the grounds as I can access them...
I have had
C1278
U1016
U1094 (a lot!)
U1064
B1001
--516 the VSS code - it, and its wire, checks fine.
Both sets of O2 sensors - I think I solved them
At the moment the flickering CEL does not set a code - just stumbles the car...
The BCM is dry and clean...
I will check the doors...
I really did do all the "free" things first
As I get "fresh codes" I will report
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have been chasing an electrical gremlin for about 4 weeks in a 99 FRC. It has not been in the rain (drought here in GA anyway) but in the garage.
I know I have a right front turn lamp socket with a short (new front light harness should be here tomorrow at ten) all the other grounds/harness look good - BUT...
There has not ever been a battery leak and all looks good under the battery now.
I can get a CEL flash and a stumble when I turn the wheel left with vigor and sometimes I get a CEL flash and stumble when I hit a bump - especially when turning left. Lately, I have gotten code C1278 and "Service Traction Control" with some of these "stumbles". We replaced three out of 4 wheel bearings last weekend due to play (this is a NASA TT car).
The dash seems to lose power for a second and the Tach/Speedo do a "mad sweep" for a second before returning to normal - car loses power and then recovers. Resets the avg MPG also
Based on a RAFT tip we will check the IPC ground tomorrow also.
Could this be a steering sensor?
Any tips or advice greatly needed.
I know I have a right front turn lamp socket with a short (new front light harness should be here tomorrow at ten) all the other grounds/harness look good - BUT...
There has not ever been a battery leak and all looks good under the battery now.
I can get a CEL flash and a stumble when I turn the wheel left with vigor and sometimes I get a CEL flash and stumble when I hit a bump - especially when turning left. Lately, I have gotten code C1278 and "Service Traction Control" with some of these "stumbles". We replaced three out of 4 wheel bearings last weekend due to play (this is a NASA TT car).
The dash seems to lose power for a second and the Tach/Speedo do a "mad sweep" for a second before returning to normal - car loses power and then recovers. Resets the avg MPG also
Based on a RAFT tip we will check the IPC ground tomorrow also.
Could this be a steering sensor?
Any tips or advice greatly needed.
There are a TON of electrical connectors outboard of the battery. Give them a close look.
BC
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
A small rubber mallet may be what is needed to isolate this issue. Have someone watch the Cell light while you agitate various items with the mallet. Also flex and twist EBTCM wiring harnesses. Especially the main harness on the EBTCM. The steering column is a PRIME area of concern and often has chaffed/pinched wires and loose connections.
There are a TON of electrical connectors outboard of the battery. Give them a close look.
BC
There are a TON of electrical connectors outboard of the battery. Give them a close look.
BC
I did find a where it looks like my new RPM transmission
is leaking back by the differential and it looks like my oil cooler block is up to its old tricks of leaking again - but nothing, I can locate, seems to be doing the electrical gremlin.But when I took it out for a ride - it lost power for a millisecond (easy to tell since the avg mpg freezes in the single digits) but no CEL. A few minutes later I was able to get the CEL to come on, service tractions control and it threw only the C1278 H code with a sharp left turn of the wheel.
Last edited by varkwso; Jan 12, 2008 at 12:26 PM.
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Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
Victory, of sorts, I was able to get the car to stumble and change idle. I had a welding glove on and pulled on the harness leading to the starter along the passenger firewall.
The car threw the following codes
U1016 H
U1064 H
U1094 H
when the headers cool I should be able to start checking that bundle ...
I really hope this is the problem!
The car threw the following codes
U1016 H
U1064 H
U1094 H
when the headers cool I should be able to start checking that bundle
...I really hope this is the problem!
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
I really hope I found the problem. The harness ground on the passenger side of the engine was broken inside the insulation (I may have pinched it in the recent engine swap - who knows) but would be in contact most of the time. I had checked it once already but not with the engine running.
It was a real booger to get to and repair with headers on the car but it has not done it again since I repaired it today
If I am lucky it will be fixed now
.
Thanks for all the advice and encouragement
...
It was a real booger to get to and repair with headers on the car but it has not done it again since I repaired it today
If I am lucky it will be fixed now
.Thanks for all the advice and encouragement
...
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
I've been struggling with a C1287 myself for a while. Like you I think it may be a SWPS issue. Unlike yours, mine comes on straight and level. In fact I get it most often when I stop at a light. On Bill's advice I tried the AH connectors at the hubs. I cleaned them up and its been better since but not completely fixed. I may yet have to change the sensor but you may have more than just the ground issue.
BTW, looks like from your banter you may have done a tour at LH or UH?
BTW, looks like from your banter you may have done a tour at LH or UH?
Last edited by DeeGee; Jan 12, 2008 at 04:44 PM.
Thread Starter
Le Mans Master
Joined: Oct 2002
Posts: 6,855
Likes: 2
From: Grovetown GA
I've been struggling with a C1287 myself for a while. Like you I think it may be a SWPS issue. Unlike yours, mine comes on straight and level. In fact I get it most often when I stop at a light. On Bill's advice I tried the AH connectors at the hubs. I cleaned them up and its been better since but not completely fixed. I may yet have to change the sensor but you may have more than just the ground issue.
BTW, looks like from your banter you may have done a tour at LH or UH?
BTW, looks like from your banter you may have done a tour at LH or UH?
77th Tactical Fighter Squadron at UH.....amongst others...