My car's been down with a bad fuel pump, so I have not addressed my ABS module/P1637 problem. I agree that pulling the tank is triple tough with the car on jack stands.

Last week, I sent the ABS/TCM module to Automotive Scientific @ Rogersville, TN. They said my module was fried, but they're sending me an identical one with a lifetime warranty.

One of my wife's neighborhood kids in Memphis ended up being a Jag dealership mechanic, and he's going to address the fuel tank. I've just got to figure out how to get the XK8 on a car trailer for the 135 mile trip.

Automotive Scientific says they're very experienced with Jag modules. I told him my daily driver is a Lexus, and they said they've never seen a Lexus ABS module. They've just seen a few Lexus ECM's over the years, even. I guess some modules are engineered better than others.

 

First I would like to say thank you for all of the information. This forum is a wealth of knowledge. I currentl have 2 Check engine fault codes: P1111 and P0701 ABS light with Cruise control unavailable. Prior to yesterday ABS/ Check engine light/ and gearbox fault was displayed and the car was in restricted permance mode. I cleaned the Wheel Speed Sensors, started the car back up and drove it around. All lights went off. Today after about 40 miles ABS/ Check engine light came back on, but has not yet displayed the gearbox fault and seems to be driving normally. Any information/ advice would be appreciated. Thanks

 

If the ABS light is on, you are driving without the benefit of ABS assist. It will not hurt the car, but is less safe. There are tons of threads on this issue, including in the DIY sticky at the top of the main page.

The check engine light is not necessarily related and bears further research. Pull all the engine codes and someone on the forum can get you more help.

Just for fun, have your battery checked. These cars are very sensitive to low voltage and may be throwing codes because of that.

 

I'm having a similar issue and an ABS rebuild did not help, some info on the issue:

ABS with a circle around it comes on when turning on the ignition. The TRAC error message usually comes on after. Both go away by themselves. There is also some slight lurching at times where you put the pedal down and there is no response with the ASC light blinking. Removing the ABS module removes the lurch. I also get error message: P1637.

What I've done:

- Checked sensor resistances, they all check out.
- Rebuilt module.
- Cleaned wheel speed sensors (Should not matter since it's on right away)
- Checked battery voltage at idle when the ABS light is on = 14.5V (2 year old battery).
- Connection to ground and battery poles tight.
- Checked ABS cable slack on both LF and RF.
- ABS reset (neg touched to pos).
- Cleaned ABS sensor connectors.

Still have the problem. I guess check the front harness more thoroughly or connectors?

 

When you remove it the lurch goes away. Humm sounds like an issue with ABS repair. I used modulemasters.com. That was a repair over 2 years ago with no issue. Cross fingers.
Also on the harness issue. I used the battery test and I rotated the plug. I did see where the power did drop. Have you tried that?

GAMEBLASTER1

 

Ok some updates:

Got codes pulled for $90:

C1155 - Front left wheel speed sensor circuit failure (so sensor or harness?)
C1145 - Front right wheel speed sensor circuit failure (so sensor or harness?)
P1637 - Can engine control module / ABS module /network malfunction
P1799 - Can transmission control module / ABS module circuit / module circuit malfunction

My hypothesis for the now rare lurching: it only engages when ABS is working, and driving around you get a open circuit, making the small ASC light flash, confusing the car, making it lurch. Could that make sense?

Shop recommended replacing front left and right sensors, but I figure I should test the harnesses first with the 9V test as you suggested. So that's next, thanks for the input!

 

Did resistance and voltage test for front left and right harness:

Resistance: ~1.1kOhm for both sensors.
Voltage: same as on battery for both harnesses, not changing if twisting/moving the harness/connectors.

Is there any way it could be the sensors? Is the resistance too low? I'm a bit confused, should I get a used pair?

 

There's also a guy here: ABS/ DSC System Fault who seems to have had an identical problem, with techs finding wheel speed sensor errors, resistances checking out and it turning out to be the module.

 

I couldn't get rid of a open circuit fault to the left front, so I bought a used module. Problem resolved.

 

Just a thought ... Many people repaired the ABS module themselves, and there is a SMD resistor or diode that gets dislodged from the circuit board next to the repair point. It can happen even with the most careful opening of the plastic case. I know mine did . Sigh. If you reopen the ABS module look for that tiny component not quite attached.... It will be close to the edge. CAREFULLY resolder that SMD with TINY solder and a sharp *****. Barely touch the SMD for a few seconds at a time and use a very low voltage pencil type soldering gun.

Good luck! Mine works great now! No. More intermittent lights.

An obdll tool can be purchased on Internet for $30-50 USD. Just connect to laptop. Or even iphone app! Another $30-90 and real- time monitoring of fuel rails, pressures, timing, true RPMs etc.

Have fun fellow computer geek !!

Robert in Atlanta

 

My ABS/traction control problem began as an intermittent warning that became more frequent. Now I know that this was caused by the solder joints in the module as they degraded and then totally failed. At this point the ABS/traction control warning was on any time the ignition was on.
With advice from this forum, I opened the module and soldered the two connections inside. The problem disappeared immediately and has not returned.

 

any chance you took some close up pictures of the procedure

 

I like this method, but you either need another pair of hands to hold the abs, or better yet, a drill press.

JagRepair.com - Jaguar Repair Information Resource

 

I did this myself and no drill press. You need a vise. I did not take pictures but there is a very good description with great pictures of the solder joints. I think it was on this forum. Anyway, removing the module is very straightforward and I did disconnect the brake lines for access. Use a hacksaw blade and box cutter to open the halves of the module, but only cut as deep as necessary. Take your time on this part. Solder the two joints as in the picture, reseal the module closed. I gently clamped it in a vise for a couple of days. After installation, I bled/flushed the brake fluid since I'm at 100,000 miles. I did enlist my disinterested fiancee to help me with the brakes. I'm very pleased with the results.

 

Gus, I know this is from a very old ABS problem thread, but I am searching through every thread and post I can find to resolve my ABS P1637 DTC and other other issues.

But my question is not about the ABS problem. It is about your instructions for doing a "HARD RESET". I have done those resets many times over the past 13 years I have owned my '97 XK8. I do not think I ever connected or pressed the ground cable to the "+" cable while it was still connected to the battery. I have always disconnected both cables and linked them together, thereby getting what I assumed was a hard reset (same window reset issues required, etc.).

My question is: wouldn't grounding to the "+" battery post and cable create a dead short and damage the battery....and possibly some electrical components?????

Ken K.

 

Not Gus but my thoughts,
No short is possible with only one battery post connection.
No matter what is connected to a single terminal there is no current flow.

 

Doing the hard reset properly has not cause any problems that I know of. See the attached link. What it does is clear up any confused computers in the car.
Link JagRepair.com - Jaguar Repair Information Resource

 

Only because both you and H2O Boy mentioned it, I just received an email from AUTOENGINUITY regarding their current scanner(s). Basically, it says that NONE of their scanners can "flash", "reconfigure" or "reprogram" any modules. I was shocked because I read that theirs was THE one that could do that and re-establish the communication between the ECU and the ABS and TCM modules after a R&R.

 

Hi Gameblaster; I was wondering if your module problem ever got solved? Get rid of all your lights and faults. After the local Jag shop couldn't even find the module because there was no communication I gave up and sent it to "MODULE REPAIR PROS" in Van Nuys, CA. They returned it in just a few days, supposedly repaired and all sealed up. But they didn't include any information about what they did or what the problem was. I hate to reinstall it unless I know it's gonna work. So, it's still sitting on my desk.